We have skills, the patterns can start at the starting point or halfway in, and almost all the patterns are one rotation or leg down one side then switch to other rotation or leg. So if we're doing the second half first, we just start at that point. It annoys one of my colleagues to no end, but I start teaching a pattern (or individual turns) in the skaters perceived bad side first. For three turns, we learn LFI first, bad leg, bad rotation. Then on pattern, the second half first which is all the left leg turns. My point being, by the time they've got the "bad" ones up to a passing standard the good ones will be there.
Whereas, coaches who start off with the RFO/RFI set have great skaters for the first side and then they stop dead when they hit the other side. So the skater practices the pattern over and over, flies down one side and makes that even better and the bad side gets somewhat better. It would be a point that the judges would make on test sheet, even if both were of passing standard, that one side was weaker (not, one side was stronger).
It's okay to occasionally do the good side, in a way that you're modelling the technique to the bad side, this would be for adults self-instructing, eg, when I do this RFO, this arm is here this leg is there.... therefore if I mirror those, it should make the LFO work.....
I completely stole this teaching technique from my piano teacher who would open the book and point to a spot and say start here. Because we all started at the beginning and faltered at the nasty bits. It all had to be of the same quality.