It is possible to ride with a single rein off the bottom fitting on the bit, or even from the rope, but this is generally not recommended, because to an extent you defeat the object of applying moderate pressure to several points (nose, poll, curb, bars) and will reduce the bit to acting on possibly only one or two points.
The idea of the bit acting on several points is to prevent resistance to a sole point of contact
just watched lots of vids on the mikmar site that showed the best ways of using it with one rein.
i used to ride him with double reins on a pelham so its not a problem if thats how he likes it - but just wondered whether it was beneficial or not in one rein.
