diff --git a/examples/stackbasic/main.go b/examples/stackbasic/main.go
index 17350b1..01ea1f2 100644
--- a/examples/stackbasic/main.go
+++ b/examples/stackbasic/main.go
@@ -9,6 +9,7 @@ import (
 	"net"
 	"net/netip"
 	"os"
+	"runtime"
 	"time"
 
 	"github.com/soypat/lneto"
@@ -62,13 +63,15 @@ func main() {
 	buf := make([]byte, mtu)
 	var hdr httpraw.Header
 	hdr.Reset(make([]byte, 0, 1024))
+	const standbyDuration = 5 * time.Second
+	lastHit := time.Now().Add(-standbyDuration)
 	for {
 		nread, err := tap.Read(buf[:])
 		if err != nil {
 			slogger.error("tap-err", slog.String("err", err.Error()))
 			log.Fatal(err)
 		} else if nread > 0 {
-			debugEthPacket(nil, "IN ", buf[:nread])
+			// debugEthPacket(nil, "IN ", buf[:nread])
 			// fmt.Println("INHEX ", debugHex(buf[:nread]))
 			err = lStack.RecvEth(buf[:nread])
 			if err != nil {
@@ -85,13 +88,18 @@ func main() {
 			_, err = tap.Write(buf[:nw])
 			if err != nil {
 				log.Fatal(err)
-			} else {
-				slogger.info("write", slog.Int("plen", nw))
 			}
 		}
-
-		if nread == 0 && nw == 0 {
-			time.Sleep(5 * time.Millisecond)
+		hit := nread > 0 || nw > 0
+		if hit {
+			slogger.info("exchange", slog.Int("read", nread), slog.Int("nwrite", nw))
+			lastHit = time.Now()
+		} else {
+			if time.Since(lastHit) > standbyDuration {
+				time.Sleep(5 * time.Millisecond)
+			} else {
+				runtime.Gosched()
+			}
 		}
 	}
 }
@@ -119,10 +127,12 @@ func doHTTP(conn *internet.TCPConn, hdr *httpraw.Header) error {
 	fmt.Println("sending response...")
 	hdr.Reset(nil)
 	hdr.SetStatus("200", "OK")
+	data := `{"ok":true}`
 	response, err := hdr.AppendResponse(nil)
 	if err != nil {
 		return err
 	}
+	response = append(response, data...)
 	_, err = conn.Write(response)
 	if err != nil {
 		return err
diff --git a/examples/tap/main.go b/examples/tap/main.go
index 5aaadff..a5ac544 100644
--- a/examples/tap/main.go
+++ b/examples/tap/main.go
@@ -8,6 +8,7 @@ import (
 	"net"
 	"net/http"
 	"net/netip"
+	"runtime"
 	"time"
 
 	"github.com/soypat/lneto/internal/ltesto"
@@ -44,7 +45,8 @@ func run() error {
 	}
 	fmt.Println("listening on http://127.0.0.1:7070/recv  and  http://127.0.0.1:7070/send on hwaddr:", net.HardwareAddr(hwaddr[:]).String())
 	go http.ListenAndServe(":7070", sv)
-	misses := 0
+	const standbyDuration = 5 * time.Second
+	lastHit := time.Now().Add(-standbyDuration)
 	for {
 		result, err := sv.HandleTap()
 		if err != nil {
@@ -53,14 +55,13 @@ func run() error {
 		if result.Failed {
 			return errors.New("tap failed, exit program")
 		} else if result.ReceivedSize == 0 && result.SentSize == 0 {
-			misses++
-			if misses > 1000 {
-				time.Sleep(200 * time.Millisecond) // No data exchanged, sleep a bit to not hog CPU.
+			if time.Since(lastHit) > standbyDuration {
+				time.Sleep(5 * time.Millisecond) // Enter standby.
 			} else {
-				time.Sleep(50 * time.Millisecond) // No data exchanged, sleep a bit to not hog CPU.
+				runtime.Gosched()
 			}
 		} else {
-			misses = 0
+			lastHit = time.Now()
 		}
 	}
 }
diff --git a/examples/tcpclient/main.go b/examples/tcpclient/main.go
index 3e66368..24e4afc 100644
--- a/examples/tcpclient/main.go
+++ b/examples/tcpclient/main.go
@@ -1,6 +1,7 @@
 package main
 
 import (
+	"flag"
 	"fmt"
 	"net"
 	"os"
@@ -19,6 +20,9 @@ func main() {
 }
 
 func run() error {
+	var port int
+	flag.IntVar(&port, "lport", 13337, "Local port over which to hit server")
+	flag.Parse()
 	// Prepare GET request.
 	var hdr httpraw.Header
 	hdr.SetMethod("GET")
@@ -30,7 +34,7 @@ func run() error {
 	}
 
 	fmt.Println("dialing...")
-	conn, err := net.DialTCP("tcp4", &net.TCPAddr{IP: []byte{192, 168, 10, 1}, Port: 1337}, &net.TCPAddr{IP: []byte{192, 168, 10, 2}, Port: 80})
+	conn, err := net.DialTCP("tcp4", &net.TCPAddr{IP: []byte{192, 168, 10, 1}, Port: port}, &net.TCPAddr{IP: []byte{192, 168, 10, 2}, Port: 80})
 	if err != nil {
 		return err
 	}
diff --git a/http/httpraw/header.go b/http/httpraw/header.go
index 5372964..c340dd4 100644
--- a/http/httpraw/header.go
+++ b/http/httpraw/header.go
@@ -31,12 +31,13 @@ func (f flags) hasAny(checkThese flags) bool {
 	return f&checkThese != 0
 }
 
-// Header implements "raw" HTTP validation and header key-value parsing, validation and marshalling.
+// Header implements "raw" HTTP header key-value parsing, validation and marshalling.
 //
 // It does NOT implement:
 //   - Normalization.
 //   - Cookies (see [Cookie]).
 //   - Special header optimizations.
+//   - Content-Length validation and other special header field value validation.
 type Header struct {
 	hbuf headerBuf
 
@@ -79,6 +80,7 @@ func (h *Header) Parse(asResponse bool) error {
 
 // TryParse begins parsing or resumes parsing from a failed previous attempt from any of the Parse* methods.
 // As long as needMoreData returns true future calls to TryParse may succeed and the header is not done parsing.
+// Users may call [Header.ForEach] in-between TryParse calls so as to validate values before header is completely parsed.
 //
 //	needMoreData := true
 //	var err error
@@ -306,7 +308,7 @@ func (h *Header) getNonEmptyValue(s headerSlice) []byte {
 	return h.hbuf.musttoken(s)
 }
 
-// AppendRequest appends the request representation to the buffer and returns the result.
+// AppendRequest appends the request header representation to the buffer and returns the result.
 func (h *Header) AppendRequest(dst []byte) ([]byte, error) {
 	if h.flags.hasAny(flagOOMReached) {
 		return dst, errOOM
@@ -333,7 +335,7 @@ func (h *Header) AppendRequest(dst []byte) ([]byte, error) {
 	return append(dst, strCRLF...), nil
 }
 
-// AppendResponse appends the response representation to the buffer and returns the result.
+// AppendResponse appends the response header representation to the buffer and returns the result.
 func (h *Header) AppendResponse(dst []byte) ([]byte, error) {
 	if h.flags.hasAny(flagOOMReached) {
 		return dst, errOOM
diff --git a/http/httpraw/parse.go b/http/httpraw/parse.go
index a973dc1..8e258b4 100644
--- a/http/httpraw/parse.go
+++ b/http/httpraw/parse.go
@@ -222,6 +222,9 @@ func (h *Header) peekHeader(key string) argsKV {
 
 func (hb *headerBuf) mustAppendSlice(value string) headerSlice {
 	L := len(hb.buf)
+	if L == 0 {
+		L++ // Valid key-values start after 0.
+	}
 	copy(hb.buf[L:L+len(value)], value)
 	hb.buf = hb.buf[:L+len(value)]
 	return hb.slice(hb.buf[L : L+len(value)])
diff --git a/internal/backoff.go b/internal/backoff.go
index ae58d97..8aa88dd 100644
--- a/internal/backoff.go
+++ b/internal/backoff.go
@@ -7,6 +7,7 @@ type BackoffFlags uint8
 const (
 	BackoffHasPriority BackoffFlags = 1 << iota
 	BackoffCriticalPath
+	BackoffTCPConn
 )
 
 func NewBackoff(priority BackoffFlags) Backoff {
@@ -14,6 +15,10 @@ func NewBackoff(priority BackoffFlags) Backoff {
 		return Backoff{
 			maxWait: uint32(1 * time.Millisecond),
 		}
+	} else if priority&BackoffTCPConn != 0 {
+		return Backoff{
+			maxWait: uint32(5 * time.Microsecond),
+		}
 	}
 	return Backoff{
 		maxWait: uint32(time.Second) >> (priority & BackoffHasPriority),
diff --git a/internet/tcpconn.go b/internet/tcpconn.go
index 7904d43..112b2af 100644
--- a/internet/tcpconn.go
+++ b/internet/tcpconn.go
@@ -135,7 +135,7 @@ func (conn *TCPConn) Write(b []byte) (int, error) {
 	} else if plen == 0 {
 		return 0, nil
 	}
-	backoff := internal.NewBackoff(internal.BackoffHasPriority)
+	backoff := internal.NewBackoff(internal.BackoffTCPConn)
 	n := 0
 	for {
 		if conn.abortErr != nil {
@@ -171,7 +171,7 @@ func (conn *TCPConn) Read(b []byte) (int, error) {
 	}
 	conn.trace("TCPConn.Read:start")
 	connid := conn.h.ConnectionID()
-	backoff := internal.NewBackoff(internal.BackoffHasPriority)
+	backoff := internal.NewBackoff(internal.BackoffTCPConn)
 	for conn.h.BufferedInput() == 0 && conn.State() == tcp.StateEstablished {
 		if conn.abortErr != nil {
 			return 0, conn.abortErr
diff --git a/tcp/handler.go b/tcp/handler.go
index 1b2b90a..ee1a052 100644
--- a/tcp/handler.go
+++ b/tcp/handler.go
@@ -2,6 +2,7 @@ package tcp
 
 import (
 	"errors"
+	"io"
 	"net"
 
 	"log/slog"
@@ -108,6 +109,7 @@ func (h *Handler) OpenListen(localPort uint16, iss Value) error {
 // Abort forcibly terminates all state associated to current connection.
 // After a call to abort no more data can be sent nor received over the connection.
 func (h *Handler) Abort() {
+	h.info("tcp.Handler.Abort")
 	h.scb.Abort()
 	h.reset(0, 0, 0)
 }
@@ -215,8 +217,14 @@ func (h *Handler) Send(b []byte) (int, error) {
 	}
 	buffered := h.bufTx.Buffered()
 	if buffered == 0 && h.closing {
+		// If Close called and no more data to be sent, terminate connection!
+		h.closing = false
 		err = h.scb.Close()
-		h.info("tcp.Handler:Close", slog.String("scb.Close.err", errstr(err)))
+		if err != nil {
+			h.logerr("tcp.Handler.Close", slog.String("err", errstr(err)), slog.String("state", h.State().String()))
+			h.Abort()
+			return 0, io.EOF
+		}
 	}
 	offset := uint8(5)
 	var segment Segment