When I was reading up on refinement I saw this: You can’t have a +3 bonus until you also have a +2 and a +1. If you have two bonuses at +2, you must have two more at +1, etc. (p182)

So If a character has Evocation and he chose water as the spec and took control +1,(water)
                                            2 free item slots for water-gun +1 power,+1 control (water)
this is fine so far because it is Water Power +1, Water Control +2.

but if I take refinement I have to specialize in a different element right?

I am trying to understand the spellcasting system. I have a player that wants soulfire at -6 and mark of power at -1. It is a -7 refresh game. Is this even allowed? Please help!!!