The smaller package gives you greater control.
The more I field dress deer, the handier i really feel a smaller knife is. Knowing exactly what you're cutting, you can make short work of a white tail with a small knife and do a pretty clean job of it.
One time i forgot a knife, asked my dad to bring one (he was enlisted to help drag the heavy buck out)...and he showed up with a 10" bowie knife (he hasn't field dressed many deer). I thought he was joking at first. When I realized he wasn't i began work in the deer...trying to take care of the back end of a deer with a knife that big ISN'T a pretty sight!