A lot of cam pressure will force heaps of shape into the sail, when sailing it will feel very rigid/locked in rotation would be alot harder, softer cam pressure the sail will feel just like that "softer" and cams rotate better.

Was asking the question as last sail I had with the sail in question noticed that the mast sleeve was not tight and the sail had no drive and hard to rotate, 3rd time out on it. When back on the beach found the bottom cam was contacting the mast and the upper two were about 1cm off the mast, obviously this is not good. have since rigged at home and got some pressure on the mast which has tightened up the mast sleeve and cam seemed to rotate better then before need to try it on the water now.

if your going to use spacers be careful when derigging or you can break battens, a little bit of play isn't a problem, and always remember too let a bit of down haul off and pop the cams off by hand before releasing all the out haul