I have seen posts where people claim that John Browning used a wide slotted screw head for the purpose of fitting the base plate of his magazines allowing the 1911 to be taken down without any tools whatsoever, in the field.
This got me curious, and while I no longer have the WWII Remington Rand I once had, I still have a pre-series 70 Government model, and an Argentine Systema Colt. With them, the tip of the magazine baseplate is just a tiny bit too thick (tried several GI mags) to fit in the grip screw slot, without marring it.
I have a friend who has a 1911, and will ask him to check, but I just drove him home from surgery today, so it will be a couple days, I expect.
You need ONE "tool" to strip the original 1911 design (both the GI guns and the Colt commercial guns. This does not apply to later changes in the design, such as collet bushings, one piece guide rods, etc.
The only "tool" needed is something small enough to poke the firing pin in, so you can remove the firing pin stop. Once you do that, the entire rest of the gun can be disassembled and reassembled using only the parts of the gun and your hands as "tools"
Quite literally, unless you are naked, alone in a sand only desert, you have or can find something to poke in the firing pin. The point of a rifle bullet, the stiff tip of a bootlace, the GI can opener (which also is a screwdriver), tons of things a GI would have on or around him, or things that can be found in the environment.
The firing pin is a punch, to remove the mainspring housing pin (which is why one end of the pin is cup shaped, so as not to damage the firing pin tip), the sear spring is a screwdriver (that one leg is to turn the "screw" in the magazine catch), the hammer strut works to disassemble the magazine, and the "tail" of the follower will work on the grip screws.
The curious thing is that this was not taught at the user level, not formally, anyway, and the user is not authorized to do it, either. Higher level maintenance is where I learned the tricks, though not formally. It's neat that you CAN do this, but there's no credible situation I can think of where one would need to repair the gun the GI way (replace broken part) and have the part, but not the simple tools normally used.