Admittedly, I haven't gone back and forth during a single listening session. I have, however, before swapping in a new set of ICs, listened to the current set for a while, powered everything down, swapped cables, then powered everything back up. My concern with this method (as I have no means of "hot" swapping) is that I believe (here we go again) that my system sounds best after a warm up period of at least 15 minutes; a couple hours is better.
My other excuse, errr... rationale, for not doing a blind a/b comparison is that I don't let my family members mess with my gear, which makes the "blind" aspect rather difficult.
Please understand that I do not have so much money invested that I'll have egg on my face if it turns out that Rat Shack cables work for me. In fact, I'd welcome it - I'd sell the others off to raise funds for other audio projects! FWIW, I've spent no more than $75 on a pair of cables, new or used. Aside from the single new pair of cables I've invested in (for the princely sum of $40 or so), the others I've either purchased used (well below retail), been given promotional samples (for the cost of shipping), or been involved in beta tests. I would never have paid full retail for any of the pricier cables I've tried - one thing I agree with everyone else on is that cable vendors are among the worst sort of snake oil salesmen.
At any rate, I'm perfectly willing to do A/B comparisons, and it would probably make sense for those swaps to be done without the benefit of a warm up period. This would level the playing field so long as no one pair of cables has the advantage of a warm up period, assuming there is any benefit to be had from a warm up in the first place.
Any recommendations as to how to facilitate such a comparison are welcome.