Originally Posted by
Sixty Fiver
Shimano Arabesque derailleurs come to mind here...
I was thinking of older stuff, like Pre Index Campagnolo, Huret Jubilee and the like, all Simplex derailleurs and so on.
Situations like setting chain length is why I like to say that
there are no rules, only considerations.
Folks who learn a rule and blindly follow it get into trouble when they find the exception but don't recognize it.