As others have said there are several cons to shooting to long of a draw. Here's my personal experience..take it for what it's worth.

My wingspan is 65". I shot a 28" DL (with a string) for a couple years, though my accuracy was never great, but my bow just wouldn't adjust any shorter. Now I got a new Bowtech and had it set at 27" with brass nocks. and WOW, what a difference. It's so much more enjoyable to shoot than my older bow ever was...(now this is a result of being a better bow as well as the shorter DL).

You could probably shoot a 28" DL with brass nocks, but you might find you'd be happier if you shopped around and found a bow adjustable to 27". Check out this thread I started back in December. There is a lot of good info there and you can see a pic of me with a draw length that was too long and my new shorter draw length.

Advice for short draw