There's something worth observing about EVE Online's offline skill training design from a game development perspective: Since it's possible to train skills offline, that's what people actually do.
In other words, people will log on and play for a while to build up cash, either taking on pirate NPCs or (as I do) just mining for veldspar and scordite in 0.8 or safer space. It doesn't take long at all to make millions of ISK.
The rest of the time, players pay CCP $15/month to log in once every couple of days, select a new skill to train, and log out again. CCP gets the player's money, but the player uses virtually no bandwidth!
As a gameplay mechanic that fits a business model, that is utterly brilliant.
As gameplay... well. Not so much fun. And certainly not supportive of playing a character (as in an RPG).
But as a system for generating revenue, it is diabolically clever.