TuningSend is a notification method. You should not call it to send message, it will be called by wodBeep when new there's data ready to be sent to remote peer, so any tuninng profiles currently active can encode it the way they need to. Byte array provided through Data argument is not structured in any way - it is raw data prepared by the transport engine.

Typical example would be SSL tuning profile - before it goes out through socket it needs to be encrypted. wodBeep cannot do this by himself - and it needs to be done at raw socket level. So, after transport engine prepares outgoing packets, raw data of such packets is provided to tuning profiles through TuningSend notification so they can encrypt it and return back to transport engine.