hmmmm...having to ponder what I meant. I think I have it backwards. I think it was when I've tried using two different size circs, putting one size of each on the cables so the working needles are the same size....
I guess it was backwards...knitting on the smaller and trying to slide the stitches that were knit on the smaller needle up onto the larger one.
So...I guess it wouldn't be an issue on the dpn's because you wouldn't have to slide or transfer them onto the bigger needle.
Guess I should think through the situation before posting---I just remembered the nightmare of using two sizes and applied it inaccurately.