I'm trying to understand the difference between dedicated and current thread flags as it relates to the synchronous slave FIFO read/write timing.  AN65974 says that for a current thread flag there's a two cycle latency. It doesn't specify read or write although a two cycle latency is consistent with the synchronous slave read timing diagram.

If I use a current thread flag, do I incur an extra two cycle latency in addition to the two cycle latency shown for the dedicated thread flag?  If not whats the timing difference between the two.  

Great question Ray.  Sounds like you have an old version of AN65974 that was released before it made any sense. A new, more coherent version is now available that explains the timing and flag configuration in more detail.