So we ran into a problem today where disabling a massive amounts of inputs was really slow in IE8. It would take several seconds to disable 200 inputs. Caching the DOM elements in an array did not seem to help much. Setting the actual html attribute was the slow part.
My coworker came up with a pretty great IE hack to speed up the process of disabling and enabling the inputs:
faking it turns out to be faster then doing it the real way.