Hard to beat having a full length chain saw in a tin the size of a shoe polish tin in your thigh pocket. If weight/bulk were not a consideration, there are a whole host of foldable/stowable saws that I might consider hodding along. The fact is, when I am trudging through the forest with gun and pack, I will gladly opt for the smaller lighter container that I know will get the cutting job done just fine. If I am at base camp, or at home, and the Stihl is acting stubborn and the McCullough is in the shop, then a good bow or frame saw or even a had saw would be my next reach, assuming I haven't already framed the pocketchainsaw or the sabre saw.

Size matters, at least when it comes to my back having to haul the load through the vine maple and briar. A horse would swing the balance toward a pre-framed or rigid saw as well, but I don't have ready access to horses these days either...

Then there's guys like Dick Proenecke, of course he had nothing better to do at the time, and I don't think the pocket chainsaw was around while he built his cabin either. I'd pay gold for his opinion on more than a few things like this.
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The ultimate result of shielding men from the effects of folly is to fill the world with fools.
-- Herbert Spencer, English Philosopher (1820-1903)