sure; a low end boot, that is 2 sizes to big, buckles done up so tight that they are crushing your foot vs a boot that is the right lenght, width for your foot, flexes right for you, with a good footbed, and the upper cuff aligned right. ya, bit of a difference.
most high end boots, that fit you right, will be similar
Can better fitting higher performance boots increase edge hold on ice?
I have no doubt. Even going from the Tecnica XT (a consumer plug race boot) to the Nordica Aggressor 150 (a plug race boot) has made a significant difference in edge hold and overall ski performance. Definitely!
The aspect of this that has been so surprising to me is that I haven't felt that they beat me up in bumps, crud, and other terrain that I thought they might. Can't tell you why, for sure...
Thanks for the replies and the confirmation on this. I was skiing yesterday and was completley blown away by the edge hold I was getting on ice with my RX8s. The only equipment change I have made is boots so I assumed it might be the difference. Came out of an xwave 10 and into a speedmachine 14 went down a size--WOW what a difference.