There have been two accidents that I know of involving pilots with low
energy at a 500 foot finish. One reportedly tried to thermal up to
the finish height with partial water on board, while in gliding range
of the airport.

The answer is simple: if you're not going to make a 500 foot finish,
you have lots of energy for a rolling finish. Put the nose down, aim
for the end of the runway. RIsking anything to avoid the 2-3 minute
penalty for rolling finishes really is stupid. The sooner you commit
to the rolling finish, the faster you will get there, so it's even in
your racing interest to commit early.

I'm usually on the side of writing rules that avoid the temptation for
risky behavior, but this is an exception. The cost in points of a
rolling finish is so small that a well-prepared pilot really has no
excuse for screwing this one up. It's not like the awful decisions we
face when we are right on MacCready zero to make it over the last
stand of trees to the airport, where 600 points lie waiting.

Some more detailed advice on how to safely fly contest finishes under
US rules: (From a recent Soaring "contest corner")

http://faculty.chicagogsb.edu/john.c...t_finishes.mht

John Cochrane