Dry grass causes less of a seal for the front edge. Lowering the front skirt will give a better seal (but may push the leaves now that I think of it.) But as youve read, cutting low with the skirt in the low posy has its own problems. Thats why I mentioned letting the grass grow longer (say .5") towards the end of the season so you can raise the deck .5" and set the skirt in the low posy without hitting anything.
You'd have to be careful the first mow though just to be sure but its a pretty quick n easy job to change the skirt height to try it.
Im really just thinking out loud here though so take it with a grain of salt!