was confirmation from reliable quarters that it is indeed Mike blowing up a storm on sax on "What'd I Say" (Sydney, 1964).
What confirmation?
The mention in the 1981
Rarities sleeve notes,
"This rare gem, featuring Mike Love on wailing sax", seems like a possibly mistaken assumption by the writer (McParland?), who (I think) also was mistaken about the lead singer.
Regarding MBE's comment,
"No it is them and Brian and I discussed it. That is Mike on sax", it looks like the "discussed it" comment doesn't necessarily refer to the possibly separate claim about Mike on sax, which might be just MBE's own opinion. And even if Brian did say that Mike played sax on "What'd I Say", he may have meant that Mike usually did, not necessarily remembering who played on the Sydney concert.
Here,
here, and
here (one thread) are comments by Stebbins and others.