Update draft-ietf-quic-transport.md

Co-authored-by: David Schinazi <DavidSchinazi@users.noreply.github.com>

draft-ietf-quic-transport.md

@@ -2167,7 +2167,8 @@ that an unused connection ID will be available to the peer when sending a
 response.
 
 The number of new paths an endpoint can probe is limited by the number of
-extra Connection IDs the peer has previously supplied.
+extra Connection IDs the peer has previously supplied. Supplying a peer with enough
+Connection IDs allows it to simultaneously probe multiple paths.
 
 
 ### Initiating Path Validation