Looked it up - chapter 11 part I.3c
Sal talks about a situation that excludes a number of things for purposes of deferral (e.g. bonuses) but then that the match must satisfy 414s
somewhat the opposite of what is described here the example provided in 3.c.1 says as long as plan must pass compensation ratio percent test for the match no matter what the deferral comp def is.
You raise a valid point in regard to rate of match, but my understanding of the rate of match issue is that you can't provide a larger match % on 'more' deferral (e.g. 100% on the first 3% and then 150% on more than 3%, which wouldn't happen in this example.
that being said, I personally wouldn't write a formula like that
Sal has a big write up 11.B.5 in which, at least in my opinion, the Reader's Digest condensed Version would be: "What are you, out of your mind?"