JJF

I am by no means an expert, but should I happen to be in a situation where I should use a knife (I hope not) i would always hold the blade horizontal with the edge pointing 'out my fingers' so that I can cut either left or right just by turning my wrist. As it said above.. just like holding a sword.

I think the 'opposite' grib is especially for special ops forces that need to slice your abdomen from below, but if you face one of those guys it dosen't really matter how he holds the knife anyway....