Originally Posted by
DarkenedPaladin
Sub-spec frost is reliant on several buffs and a proc weapon. If you ever get Bryntroll, the difference between sub-frost and sub-blood is extreme. If not it is only around 3% between the two, blood usually being stronger lacking the proc.
Also, if you have low ping (60-100) You don't even need to worry about expertise cap, drop to around 15 expertise and you shouldn't notice a problem due to unholy having free GCDs
*edit*
Expertise gains ALOT if you have a higher latency/ping however, and thus capping it becomes more worthwhile depending on your connection.