LTM with DNS - logging query answers DNS_RESPONSE clientside

I would agree that DNS_RESPONSE should be giving me what I want, however, testing ahs shown that it only considers the server side conversation (F5 SNAT to Pool instance).  It will not/does not give you access to the client side header info.  I can see it plainly in traces.  A side note - it appears that F5 LTM with DNS Profile (nothing else, straight LB) does not pass through the client side DNS header on the query.  In my tests, I set my client side to no EDNS, 512bytes UDP and sent the query in.  The F5, reformulates the query and sends EDNS0 and 4096bytes to the pool member.  WHen the poolmember responds back, the F5 then attempts to send the response evaluating the client side header flags.  In the traces, I see it set the truncate flag in the header on the client side response.  The only thing I can figure is F5 is doing the "fiddling" on the client response post the iRule processing.