around 900 is the accepted constant max temp but non prolonged times above that temp it isnt a problem.
The issues seem to centre around.
1. Where and how the temp is measured is very important. some figures mean nothing, others critical
2. VCDS logging isnt reliable either (apparantly)
3. when you go mapped the tuners can and do alter the temp values / hardware protection mapping, so what you think you are seeing generally cant be relied upon.
I found this post useful (K03 but still relevant)
http://www.golfmkv.com/forums/showthread.php?t=115731(ignore the usual APR/REVO fanboys/bunfights)
So in essence.
1. you could have an issue that causing too high EGT's
or
2. logging makes it look like you have an issue but in reality you dont.
REVO themselves should clarify the block to use and what numbers are good/bad