Of course of have, but a tac folder is a knife that is designed to aid in self preservation. A SAK isn't for that purpose.
I know that. 
Chris said " If all I had was a SAK and circumstances demanded it, I'd use it for self defense ". He has said nothing about a SAK being made for that purpose or about it being good for that job, just that if he had to, he would use it.
Of course a Tac folder would be better, but although highly limited, a SAK could be used for defence (ie slashing
) if needs must. Personally my theory would be LEG IT!! first, but if it came to it, why not.
In a desperate situation, anything in the hand is better than nothing!
Any of the bigger SAKs can be used as a fistload.
If the SAK has a backspring Phillips, it can be folded out and held so it protrudes forward between middle fingers.
The tip of the Phillips will greatly concentrate the force of any punch delivered to an opponent.
Of course OHT has lots of defensive capability, with its locking blade, locking prybar, and backspring Phillips.
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