Did I mention that Bob Haney is all kinds of awesome? From
World's Finest #217:

I don't think I'd measure up very well in this kind of comparison. This is just asking for a poor self-image. I'd think this would more likely appear in one of those silly women's magazines with "
How Does Your Man Stack Up to Superman or Batman? Not Very Well, Does He? Use the Results of This Quiz to Emotionally Cripple Him! He Deserves It Because He Has A Penis!"
Anyway, Metamorpho appears in this ish, and Metamorpho is awesome because he was the first person to turn down membership in the Justice League, and never thought twice about telling Superman to get over himself:

Super Freak! Super Freak! He's Super Freakayyyy!
He also shows up Batman in this issue, which uncharacteristically annoys Bruce to no end:

You remember yesterday how I was talking about character continuity and how Bob Haney just didn't seem to care about it? This is the sort of thing I was talking about.
Now, mark how pouty both Supes and Bats have been up to this point. Got it set in your melon? Good.
Now, take this in:

Okay, obviously this is a ruse, and I get that. But look at Batman's private thoughts as he fights 'Mo:

You see what I mean? Even if he's faking (which Bats later says he is), you can't deny that his thoughts are more than a little vicious and that isn't explained away by a simple, "Oh, we were just funnin' with ya!"
Not to mention that whole, "Batman swore to never fire a gun" thing apparently doesn't apply to jet cannons, or atomic tanks:

I don't think Bob Haney ever read a Batman comic in his life before he wrote these stories. I really don't. I suppose one could say the same thing about Superman, but I've always thought Supes was a bit of a jackass, so I think Bob just had the guts to portray DC's golden goose in a way no one else up to that point had the nerve.
So, we explain everything away, and it's all good:

Except, of course, the sneaky plan didn't come about until after Superman had been all "screw you guys, I'm going home" and Batman had pitched his little fit about not getting medals like 'Mo, so that hackneyed plot device did absolutely nothing to repair that damage. But Bob Haney doesn't care, and he suggests you don't care, either.
Bob Haney. He cares not for your decades of character development. And what's more, you can't make him care. Bob Haney: Badass.