But when someone tries to attack such a password, as long as whatever the user devised isn't represented by an entry in the attack dictionary, the attack strategy falls back to brute force, at which point a repetition scheme is irrelevant to attack time. Granted, if I were creating a repetitive password to meet a length requirement without high mental load, I'd repeat a more interesting part over and over, not a single character.
If cracking techniques catch the concatenation of those as suffixes to short undefined things, which I think many people would do at minimum, that would be worrisome indeed.
