I know that every time I have to use it (which isn't very often) I have to look up WTF each switch does in the manual because there's no way I'll ever remember what "hard", "soft", and "mixed" are supposed to mean.
I will say, I personally rarely use --soft, it's either the default --mixed, or --hard in a more 'severe' case, so it's a bit easier for me to remember the roles and the relation to the flags.