I was a steward for the NHC 1st round in Denver (this was my second year). I tried to check the advanced to mini BOS box (I was probably successful 80-90% of the time). The beers that placed in the top three definately got that included on their sheets.
Most of the ones that went to the mini BOS were above 34 (one exception was a 31). I think the highest score I saw (I was there for all three sessions) was 45 (there were probably less than 10 above 42 in the styles I assisted with).
The mini BOS's were crazy affairs. The judges worked very hard to give the beers on the bubble a fair shot. I can also tell you that the highest scored beers didn't always win the day in the mini-BOS (probably 50-50), but probably the highest scored beer was in the top three or four (including honerable mention in some cases) in the mini BOS nearly all (95+%) of the time, and thus advanced.
I would agree that there were a lot of beers scored in the twenties (or below), but am conflicted about raising costs to try to get people to think twice to enter. Some people don't live in a bastion of homebrewing and don't have access to local competitions, so if they are going to ship beer to one event, why not this one?
I probably have more problem with people shooting for Ninkaski with the shotgun approach. The shear number of entries makes the competition less managable (less fun, more work, more difficult to find the number of qualified judges and other volunteers necessary) and more difficult to ensure the best beers advance. If you are a good brewer, chances are you are a great taster, so why not choose the best of your best for NHC? I am more impressed by the brewer who made a beer, tasted it, figured it pretty good, and entered his one beer to a competition and wins a medal. That's batting 1.000! I would rather see a three or four beer limit per member.
The other alternative to improve the quality of entrants is making the NHC a single round invitational and requiring your beer to place in a qualifying BJCP sanctioned competetion within the last 12 months to enter nationals. The problem with this is that it again favors those who are more involved in competitions and not some odd guy with one great beer at its peak in April.