A couple questions for Kurt if he feels like it:
- Did Louise Simonson consult you before using Kaleb in the modern-day Post-Crisis?
Was that Louise? I had it in my head, somehow, that it was Michelinie. And I don't think I read those apparances.
In any case, Paul Ryan, Kaleb's co-creator, checked in with me first about using Kaleb -- he wanted us to do a Kaleb mini, but I had no time and DC wasn't that interested, so he asked if it would be okay if Kaleb was brought into the book he was doing at the time.
I was fine with it -- but we didn't really talk about what Kaleb would do, just whether it was okay to use him.
Why would Superman be generally unworthy to lift Mjolnir? Is this a function of some particular Post-Crisis characterization. Would, say, Pre-Crisis or Kingdom Come Superman have such a constraint?
I don't think we ever said either way whether he'd be generally worthy or generally unworthy -- just that he was worthy once, and not worthy shortly thereafter -- and admittedly, picking up the hammer to return it to Thor isn't an inherently worthy purpose, not when there's no danger and he's standing right there.
The reason we did that bit was because neither Tom Brevoort nor I liked the long, long list of people who'd lifted the hammer over the years, so we wanted to introduce the idea that "worthiness" is not steady-state, it varies according to circumstances and purpose, as well as the character's worth, by whatever Asgardian standards the hammer's spell recognizes as worth. Just because someone picked it up once -- or twice, or a dozen times -- does not mean they'll always be able to do it.
As for what exact parameters factor into things, I don't think it should ever be fully spelled out -- the hammer is godly and mythic, and there should be an air of mystery about it to some degree. It's not a science-fiction weapon whose workings are mathematically transparent to human minds, so you could say, "Well, so-and-so saved a busload of children in 1968, so therefore he can lift it."
The only way to know is to try it and see. And then the only way to know if you can do it again is to try it and see again. That would go for everyone, not just Superman (including pre-Crisis Supes, Earth-2 Supes, Kingdom Come Supes, Twinkie-ad Supes or any other). I think the only guy who the reader should expect can always lift Mjolnir is Thor, and I'm not opposed to surprising them there, either.
kdb