Ideas on how to measure performance hit of SSL on a VIP?

I did that (traces on inside and outside F5 interfaces, and just in front of a desktop client) when I first posted this. I found it extremely difficult to match up the traces and timings because the traffic is all encrypted (outside the F5 and desktop), but was able to determine that out of 5 instances I could find the "pattern" of packets and packet-sizes and line them up, the data was being delivered to the desktop sub-second, leaving the only place for the performance bottleneck to be in the PC and/or the Browser, or it's ability to render the page. I've been looking for a re-usable and bullet proof way of confirming that for more data samples: something I can take to my web developers to prove it's not in the network components which they're absolutely convinced it is. Yes, the classic Application <--> Network finger pointing match.