liners - the "inside job"? (an all sports issue?)

yes, this is an all sports issue, excepting those done barefoot. :)

in skating, skiing, cycling, ... ballet even:
is the liner inside your sport shoe..., the "liason first officer", between you
and your exceptional sport performances? certainly yes!
don't use counterfeit sport shoes, or counterfeit liners inside your skates...,  if performance
is what you are after.

ex: what could one say about the compressibility of his skates' liner, if  soaked in 
      perspiration? how might this affect his overall skating performance?

liners, inside all our sport shoes (any detachable parts, shoelaces even) - do we really know
how to replace &/or customize them, to improve our performance? 

be advised, some of the detachable parts could require custom re-engineering:
a. a choice of other materials, than the initial ones, could be beneficial.
b. remodeling the inside of a sport shoe (not a simple task, although may appear as such.)

sorry, further suggestions here, would only be given directly to those interested (e-mail)