"Can you save an onsight by down climbing?"

In some local communities it is a common practice to actually work on an onsight by climb up and then reverse to the ground even if you have clipped some quick draws. The ones taking it to an extreme can come back the day after or even one year later and then ask a friend to put up the rope at the highest down climbed position! The 8a recommendation says it is OK to do it once if you have messed up the sequence or found some wet holds etc but you should not do it systematically. In competition climbing you can not step down even if you are just 10 cm above the ground and there are also some conservative who think this "rule" should also apply on rock. 8a suggest you to stay in between these two extremes.