Psuedo-philisophical question that I originally saw applied to Black Sabbath in a book.
In your opinion, how many band members would have to change for Iron Maiden to no longer be Iron Maiden to you?
I'll preface by saying that I hope the lineup never changes again. I think they have the magic formula and right chemistry as musicians as they are today.
I consider Steve Harris to be essential: No 'Arry, it ain't Maiden
Otherwise, I would consider Bruce Dickinson or Adrian Smith demonstrably beneficial, but Maiden has been Maiden in the distant past without either of them. I consider the Bayley era a bust, and a Stratton or Di'Anno reboot would likely fall flat once the novelty wore off. Without a Smith and Dickinson (sounds like a whiskey), however, it'd be a lesser Maiden, but Iron Maiden it'd remain. I consider any two of the current three guitarists key, so an Adrian departure has a cumulative effect if it coincides with another guitarist leaving. Let's call it the "dual axiom" -- see what I did there?
Dave Murray -- longevity (and skill) counts, but, sadly a Dave Murray departure on his own wouldn't be the end of Iron Maiden as we know it; however, dual axiom applies.
Nicko McBrain has said he'd want Maiden to carry on if he were somehow ever unable to play. The late Clive Burr was in my opinion great for the band's early sound; so, a non-Nicko drummer could work. I think a Nicko-less Maiden would be at a huge disadvantage (but still Maiden).
Janick Gers, not to be a stereotypical hater jackass about him but a Janick departure on his own would have little to no effect (go back to a five set); however, since any two guitarists leaving would make a difference, he's a factor if Adrian and/or Dave also left.
So, I posit that for Iron Maiden to remain Iron Maiden and not a band that happens to have rights to the name, they'd require at least Steve Harris and two out of three of the current guitarists in the lineup (factoring in replacement vocalist and/or drummer as circumstances dictate).
Now, what if Adrian or Dave (but not both), Bruce, and Nicko left and formed a band together with another bassist and one more non-Maiden guitarist? They wouldn't have the rights to the name, but how much would they be Iron Maiden?
Feel free to call this a stupid exercise or even sacrilege, but it's meant to be fun. There's always the never boring topic of prognosticating what the setlist will be in 2019 to go back to.
Cheers,
Professor Cartenhorses
p.s. Yes, I'm drinking when I post this stuff