grammar - How much not better than average is enough?

This is adapted from a silly conversation I had about a baseball player. It set me wondering how to describe this sort of wordplay linguistically.

HIM: Do we leave Jay in center?
HER: He's pretty good.
HIM: Better than average maybe.
HER: Not much better than average ...
HIM: Better than not much better than average, I think ...
HER: But not so much better than average that he's much better than average ...
HIM: Enough better than average.
HER: Exactly.

Typography in writing, representing prosody in speech, make it easy enough to sort out what's going on here. But how do you explain it in terms of a linguistic which confines itself to what is verbally expressed?

• How does “traditional” grammar analyze and describe these shifts in scope?


• Are these terms and concepts readily understood by, say, high-school students or moderately advanced EFL students?


• Does any “modern” grammar afford better terms and concepts?