I Like Guthooks! I have used a Browning folding skinner with a guthook blade for years and can't remember how many deer I've dressed with it. The biggest thing it does (for all you naysayers out there
) is help keep you from cutting into the rumen accidentally but allow you to completely open the body cavity with one fell swoop. This can be a tremendous blessing when it's 20 degs and dark and you only have a small headlamp with which to do the work.
As far as weakening the blade- I can see how a poorly designed one might, but if you put the hook above what would normally be your blade profile anyway, you have actually added material to the blade, not taken away- right?
I've made a grand total of one guthook but will make more. I can say that you need to keep the hook area larger than you think the average hide would be. I would think 5/32 would be good or slightly larger. The next one I make will be larger hooked than my first.
I have a question Dave - Ya'll Florida crackers don't eat the tenderloins(Psoas minor) of your deer? Man, that is the best part of the animal! You gotta open that booger up and get those out! But if you bust the rumen - forget about it....hence all the more reason for a guthook