I take horrible ukemi for iriminage (I always seem to not keep the ukemi tight and am far away from nage and it's not nage, it's definately me!). Ironically as nage, I can be in the proper position, but tend to loose uke when time to complete the technique.
So yes, I do think there is definately a correlation!
How can I change my ukemi to stay closer to nage? Bad habits are hard to break.