Another reason for mismatched tips on Denise is that it's easier to knit with them that way. I've always found Denise tips to be less than easy to work with. Knitting from
a smaller tip helped.
I think that if you're willing to slide stitches back and forth on a circ you might start with an I cord even.
This method might work just for starting, but I think I'd use a size smaller needle as the stitches seem to be larger than in regular knitting. http://www.youtube.com/watch?v=lPGXNoG0fjA
Just some thoughts. Either way might be more trouble than it's worth. I dunno.