Actually, you "can" go above your skill cap, whether it is 700 or 720. The way you do that is with items that have skill increase on them. As an example, using a crystalline ring or alchemists bauble to add to magery, a bracelet with +X amount to swordsmanship (or any skill) WILL allow you to go above your skill cap. I have a character that with items and jewels has something around 780 skill points. However, without using such items, you are locked into whatever your account age total skill points allow.