Comment changes suggested by @harrishancock.

c++/src/kj/async-io.h

@@ -113,7 +113,10 @@ public:
   // work early when it is detected that no one will receive the result.
   //
   // Note that not all streams are able to detect this condition without actually performing a
-  // write(); such stream implementations may return a promise that never resolves.
+  // write(); such stream implementations may return a promise that never resolves. (In particular,
+  // as of this writing, whenWriteDisconnected() is not implemented on Windows. Also, for TCP
+  // streams, not all disconnects are detectable -- a power or network failure may lead the
+  // connection to hang forever, or until configured socket options lead to a timeout.)
   //
   // Unlike most other asynchronous stream methods, it is safe to call whenWriteDisconnected()
   // multiple times without canceling the previous promises.

c++/src/kj/compat/http-test.c++

@@ -27,7 +27,7 @@
 #include <map>
 
 #if KJ_HTTP_TEST_USE_OS_PIPE
-// Run the test using OS-leve socketpairs. (See http-socketpair-test.c++.)
+// Run the test using OS-level socketpairs. (See http-socketpair-test.c++.)
 #define KJ_HTTP_TEST_SETUP_IO \
   auto io = kj::setupAsyncIo(); \
   auto& waitScope = io.waitScope
@@ -2565,7 +2565,7 @@ private:
   kj::Maybe<kj::Own<kj::PromiseFulfiller<void>>> onCancelFulfiller;
 };
 
-KJ_TEST("HttpServer disconnects ") {
+KJ_TEST("HttpServer cancels request when client disconnects") {
   KJ_HTTP_TEST_SETUP_IO;
   kj::TimerImpl timer(kj::origin<kj::TimePoint>());
   auto pipe = KJ_HTTP_TEST_CREATE_2PIPE;