A long time ago, when Crosby, Stills, Nash & Young were around, all four of them, I got into a discussion with somebody about how these four guys had all gotten together. I knew that Crosby and Nash had worked together, and also Stills and Young. I mentioned Stills and Young first, and the guy I was talking to said "Yeah, they were in Buffalo Springfield together". I knew Stephen Stills was in Buffalo Springfield, but not Neil Young. But the guy seemed to know what he was talking about, and it did check out later.
And I mentioned Crosby and Nash, and he said they were both in The Hollies. I knew that Graham Nash was in The Hollies, but not David Crosby, but again, since the guy seemed to know his stuff, I didn't question. Whenever I heard "Long Cool Woman in a Black Dress" on the radio, I assumed that that was David Crosby singing. It sounds like it could be a very young Crosby, with lots of echo or reverb or whatever that is.
But I had been led astray. David Crosby was never in The Hollies, and that's not him singing this song.
TLDR version: David Crosby was never in The Hollies, and that's not him singing this song.