I keep meaning to ask this question, every time I see a movie from the period (roughly 1960s through 1980s) where the opening credits are shown superimposed over an opening scene — but, every time text is on screen, the scene is freeze-framed. Then the text goes away and the scene starts moving again. Then it freezes again for the next credit text. And so on.
What's the story of this opening-credit style?
I'm wildly guessing that it might have originated with technical limitations, where it was easy to superimpose text over a still frame (and then duplicate that frame for a second or two) but somehow more difficult to superimpose text over a series of moving images? If that's the case, what new technology enabled superimposing text over moving images? And if it was a technological issue, would that correlate with this style of credits' dying out in "A" movies while persisting longer in low-budget films? (But I don't know how to square any of these guesses with the fact that superimposing text over moving images was ubiquitous in the 1940s and '50s. E.g. The Lusty Men (1952) or The Set-Up (1949).)
The Producers (1967) is one example that comes to mind, although it's already stylizing/subverting the trope. (See examples at 1:40, 2:10, 4:13, and 5:00 in that clip.)
Brothers (1977) is the one that brought the question back to my mind today. Sadly I can't find a clip of their credits sequence online.
I'll add further examples as I find or remember them.