I really appreciate the time and effort you all put into solving this mystery. I've been a drummer for 30 years and Clive was my main influence. I even had my set put together just like his! I consider myself an "expert" in his style and its very different from Nicko.
I've had a pet theory about his firing that I'd like to share. As you know, drummers in the 1980s had to have massive sets, whether or not they used them (eg Eric Carr). This was, of course, for drum companies to sell more product since kids thought you couldn't be "metal" without a million toms or cymbals. This I know for a fact. When Vinny joined Sabbath, he was told sternly that his 4-piece had to go. He created his famous set with all the bass drums in the background as a result. Tony makes this clear in more than one place. Huge sets were a requirement for employment.
Clive was an exception. He was an official endorser of Tama, which meant he got his drums for free. It also means he had to do what he was told. Tama was telling its endorsers to pack the stage with drums. Massive kits were required for metal. Clive refused. If you notice on the Number of the Beast Tour, they made him put octobans and the "gong" drum to his left and right, respectively. He never played them. "Octobans" were those long, small drums Tama pioneered (see the pic I've attached). Clive's set stuck out among all the other 80s metal sets and Tama wasn't happy.
Every single boot I've heard from 1982 shows Clive playing very well. No performance decline at all. There's no Nicko anywhere. His father didn't die until the end of the year, so that theory's been removed. Since his playing was demonstrably consistent, that theory is also gone. There's also no "getting used" to a new set. Drums are easily adjustable. There's no "break in" period. Even more, his tremendous technique puts the "he's not prog" theory down too. He'd be the best fit for that sort of music. No disrespect to NM, but Clive's technique was extraordinary for metal, especially his use of ghost notes that (apparently), only drummers can hear. His innovation of the very fast 16th notes on the hi-hat proves this. He was a tremendous, highly technical player.
My theory is that Tama drums, a huge music company that owns many others (such as Ibanez), was sick of Clive's refusal to bow to their demands. Paiste felt the same. Tama was a fairly new firm (1974) in a fiercely competitive industry. I distinctly recall this being an issue at the time, since I followed Clive's career like a hawk. I remember my drum teacher (Chris Goger from TT Quick) telling me about it. Given the size of the company, its influence in Japan and the possibility that he'd be dropped as an endorser, he was removed. Nicko came into Maiden already with a Sonor endorsement. That's odd. It had to have been planned ahead of time and Sonor rarely gives endorsement deals. Of course, NM had about 9 million drums around him. Sonor drums are about 4x the price of every other company because they're hand made.
Corporate backing is essential in the music business and having Clive dropped by Tama would have cost the band quite a bit, not just Clive. It just so happens that Murray often played Ibanez guitars. Losing an endorsement from a huge company is costly, embarrassing and leads to lots of equipment issues and bills later on. Back then, sponsorships were shared by the band equally. Tama was no different. In other words, he was fired because Maiden was dropped by a huge sponsor.
This is just my personal opinion, do with it as you will. I know of no one else who holds this opinion and I have no direct evidence other than industry standards and precedent. All the other theories have collapsed. Can there be truth to this? Nicko having a ready-made deal with Sonor is, however, a potent piece of evidence. Endorsements are huge for a new band and Maiden could ill afford to have the Japanese music giant against them.
