At the moment, if we get a word completely wrong , or partly wrong, we can mark it as "hard", "so-so" or whatever, but then we don't see the word until we've completed the set and then do the "redo" function. If the set has 50+ entries then by the time we re-do it we are likely to have forgotten the word anyway. Spaced repetition is supposedly a good method of aiding retention.
I don't know how other students use it, but if I get a word wrong, then having it reappear a few words down the line (while it's still, we hope, in short term memory) might help fix it in long-term memory.
What do you think?