LTM - Need TCP "write to client" time on every transaction

I've checked the Wiki up & down & would agree that getting such data at a iRule level would be difficult. Thus my question about an API or something I could hook into the TMM runtime with.

 

 

I have an official case with Support asking this question, but they are telling me this is the avenue to get an official response.

 

 

Am I to take it that BIG-IP LTM is unable to provide the write to client time such that we can determine the speeds & feeds of the client connections?