Endarire, why are you continuously posting these threads in the Min/Max forum?
Shouldn't they be in the D&D Deliberations forum?
+1, Endrarie, you have posted a number of these metaphysical questions here already. For a game that's been out as long as this one has, I find it hard to imagine that you and your group have not given these sufficient thought.
Onto the actual question: what do we mean by "efficiency" here? Based on reading through the thread, it seems you mean "build efficiency," i.e., having all your feats match up and synergize, picking the "right" spells, stuff like that. I wonder if that's what the chaos-loving friend really has in mind. If so, then this is kind of a silly question b/c one has nothing to do w/ the other other, really. Once you get to the table, you can play your god wizard chaotically or you can play your BSF chaotically, within their relative lifespans or what have you.
I think the trade-off the mysterious friend might have in mind is efficiency at the level of gameplay. Meaning, how much should we expect one to deliberate about their choices for every round, what spell they are going to cast, etc. Ideally, I like to not have to worry all that much about that sort of thing, or to worry just as much as I feel like it w/ that particular characters (some of my characters are more tactically-minded than others, some more impulsive). To that end, I put a lot of effort into making my character sheets easy to read, putting everything I need on them, that sort of thing.
I've currently been on a kick to reduce the amount of bookkeeping needed at the table, since D&D characters seem to require an awful lot of it. Some of this has been a shift to "per encounter" abilities, or just paying for them to be at will and other considerations. It's still a work in progress. Another thing to do is tone down the power of games so that one needs to pay less attention to having the "right" counter to every ability and that sort of thing, but that requires a commitment on the part of everyone involved.