The engine emits synthetic Flow events when sending messages, in addition to those raised when receiving a Flow frame for the link. I believe the reasoning for this is so to treat it as a 'credit changed' indicator. However, as there are cases where the decision to send a message has little at all to do with the credit conditions, having these events its often unecessary and wasteful.
A simple toggle will be added to signal the transport not to emit the flow events for use in those cases. The default behaviour will be unchanged.