Not sure how much of a gap there is, doesn't appear to be as big as on T-boats, etc. I've seen in the past. I agree with the possibility of getting your leg caught, and also know there's a huge chance lines will feed down through there, but I'm on my second tramp with the old style attachment. First thing, loosening up the beams on all 4 corners so you can bust your butt trying to get enough slack to slide it through the slits is a major pain! Secondly, the reason I sent my first tramp back was that the bolt rope on the back end didn't have enough material to keep it in there, and it gradually started pulling out, so I had to take it off and re-feed it back, only to have it pull out again. The solution for this appears to be to have additional material sewn along the trailing edge. Haven't put my new tramp on yet, but hopefully it will have enough material on there to stay now. I think anything is an improvement to this hastle.
JMac
Nacra F-18 #325