Fair enough. And I'll give you the vs fat part. It was unfair for me to say anyway - what was in my head when I said it was that a pound of fat is considered worth 3500 kcal, which is more energy than most things in a body. It was a shit argument that mixed points.

Overall, I think my issue is just with the simple statement that "muscles are inefficient".

The way I interpreted that statement is that "muscles waste energy", since that's all the context I could get from those words. I see muscles as super efficient, just like anything else in the body in that they do as little as possible compared to what is demanded. I view that type of laziness as ultimate efficiency.

Through the rest of the thread I got little additional context, so I kept on keeping on.

I still think the op of this thread didn't get his point across very well