LearnBoost/engine.io-client — comment on commit 2f7812ece510a2d2d8e51284f702410d94cbe70f
File: SPEC line 131
By dvv:

This renders WebSocket transport special. Also, of concern is amount of service data sent along with a bunch of short messages (which are the key ones in some setups).
I would make WebSocket transport take a payload, as other transport do. This would also help consistency.