Maybe the better question would be is the fact that a manufacturer designs and intends a “pistol” to be shot with two hands sufficient to re-classify the “pistol” into a short-barreled rifle?
Obviously, that is not the position that has been taken with handguns. Yes, they can be shot with one hand. Yes, certain manufacturers obviously have design elements intended for two handed operation of “pistols”. Traditionally and in practice, "pistols" have not been reclassified to an "sbr" based on that.
That alone is enough to show enforcement is arbitrary and capricious and that the statutory definition of a “pistol” is logically inconsistent and not being applied according to current practices.
By definition, a firearm designed and intended to be shot with two hands is not-a-pistol.
(As a thought experiment, can you imagine any modern (or archaic) pistol that is designed in a way that it cannot be shot one-handed?)
Per GCA68, if you could figure out a way to make a pistol-like-thing that requires the use of both hands, by definition that thing would not be a "pistol".
To be a short-barreled rifle, it needs to be designed to be shouldered and have a barrel shorter than 16". So that new invention wouldn't be a rifle, and the ATF wouldn't designate it as such.
The GCA68 addresses 'pistols' and 'revolvers', but does not define 'handguns' (I don't think). Since that category of firearm has not been defined by the Gun Control Act, I cannot imagine that the ATF has a position on whatever that term references.
To your final point, I believe one could extensively articulate far more foundational problems with the GCA68 and NFA of 1937 then sloppy language, such as standing in direct contradiction to the Second Amendment.
It is important to note, the GCA68 criteria for a rifle only apply to the making a designing of a firearm. Not on use, or "current practices".
If the "weapon originally designed, made, and intended to fire a projectile (bullet) from one or more barrels when held in one hand, and having:
- a chamber(s) as an integral part(s) of, or permanently aligned with, the bore(s);
- and a short stock designed to be gripped by one hand at an angle to and extending below the line of the bore(s)."
it is a pistol.
It doesn't matter what you do with it.
If you get involved in remaking or redesigning it for other purposes, it might be a rifle, if it meets the criteria during the remaking.
So don't ever intend for your pistol to be a rifle if you get the itch to remake it.
(I assure you, I never intend for my pistol, your pistol, or anyone else's pistol to be a rifle. My design intensions are all one-handed, all the time.)
% Legal and following all the laws.
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can cause issues 
