rpenmanparker 

Much of what you said in your post, OP, made no sense. Your three contact points, saddle, pedals and handlebar shoule be in exactly the same relationship on both the 54 and the 52 so the salesperson's comment is nonesense. Your leg should look the same on both bikes. If it doesn't, it is because the shop didn't set you up correctly. Similarly you should not have felt higher up on the 54, because you should have been the same distance from the pedals on both bikes. Having said that, my belief is that the 52 should be the right size for you, but you really need to confirm that by a long test ride.