Clay makes a very good point. I think I first saw if from Karl Andersen: "How well a knife cuts has to do with edge geometry. How long it cuts has to do with how good the heat treatment was." Or something similar to that
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As for that advantages of forging (hammering it to shape), I find it really fun. I like being able to move the steel into the shape I want, regardless of the shape it started out as. To me, that is an advantage-for ME. Others greatly enjoy the stock removal method and there's absolutely nothing wrong with it. As far as actual, tangible advantages on whether or not you're changing some of the structure of the steel by forging vs stock removal, I'll leave that conversation to others far smarter than I am....
A disadvantage to the forging would be equipment. Without a doubt, you have to have something for a heat source to get your steel hot enough to hammer into shape along with some other basic stuff. The things you'll need can cost a fair amount of money, greatly depending upon how much do-it-yourself you put into it.
Either way, to me it's just plain fun getting to make knives. Even after forging, there's a certain amount of stock removal to be done. I'd say if you have the opportunity, get with someone who has forged and jump in with them to see what it's like. You may find it addictive, you may find you like your current process better.
Just my 2 cents
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Jeremy