One of the problems that arose was that due to the huge speed difference it was getting harder each time to guarantee the safety of all the competitors.
There is no way to guarantee the safety of any competitor. Are you sure that's what your meant to say?
Maybe "guarantee" wasn't the right word, "manage" would be more appropriate (not a native speaker, sorry).
Anyway, the wording doesn't really matter. The point I was trying to make was that a field of 50 cats spread out over 20nm is a lot harder to oversee rescue-wise than one spread over maybe 3nm. (I should probably mention that this race was held in the spring when the water is still quite cold and you really need RIBs at both ends of the fleet.
