Yes I am saying that a Surface / Surface Pro is fine for most people - and that given the option of adding 8 cores or 8 hours of battery life most people will take the battery life.

Saying that you'll probably have a power supply nearby is fine - except for the cases when you don't - I can't count the cases when I've seen people scrambling to find power in a meeting and it's a pain and embarassing. People will take avoiding that over cores they don't need.