The objective is indeed to get a free-spinning wheel with no play, and a fraction of play is better than a fraction too tight but I've been given different advice on how to achieve it.
One Morgan expert told me he did it as you have done, ie tighten them up and then back off, the other said to just do up the castellated nut until it was just snug with a pair of long-handled snipe-nosed pliers to avoid over tightening the bearing.
Personally I use the latter method, but I don't think it makes much difference, so long as they are not so tight as to overheat the bearing, or so loose as to fail an MOT.
They are remarkably resilient and durable things. I changed mine at 100k miles mainly because I though I ought to, and the old bearings were absolutely fine when I took them out.
