A very well written rant/essay, but I'm still going to argue for the sake of arguing.
I do like the GC controller much better than the Wiimote (which is a step back to NES era when you turn it sideways) but I prefer the DualShock.
Now that that's out of the way, I think that the GC controller is more suited for button mashing more than anything as all of the buttons are extremely close to each other and as you said it is easy to press them because of hte sizes.
However, with the PS controllers, each button is at equal distance (give or take the X+Triangle and O+Square, but any developer that uses that combination is stupid) and thus it is very hard to accidentally press a different button unless you don't know what button you're going to press. This alows for more precice and careful presses. However, on the GC controler, the buttons arn't equally placed or sized for that matter. You want to press B but you're all the way at X? Well, get over there! Want to press Y but your thumb is on the C stick? Well you're screwed unless you have lightning reflexes. This is why (I think) that many games use the left analog stick as the main purpose while the right hand uses actions.
And obviuously if you bring FPSs into this and if you want to make an action but the knife button is the O button and your right hand is on the analog stick, then you'd already have to be aiming at the person and hit O as quick as you can so that's where the PS and GC controllers are similar.
But it was a pretty good "essay" though i don't agree with it fully, but i'm sure that my answer wasn't any help either.
I do like the GC controller much better than the Wiimote (which is a step back to NES era when you turn it sideways) but I prefer the DualShock.
Now that that's out of the way, I think that the GC controller is more suited for button mashing more than anything as all of the buttons are extremely close to each other and as you said it is easy to press them because of hte sizes.
However, with the PS controllers, each button is at equal distance (give or take the X+Triangle and O+Square, but any developer that uses that combination is stupid) and thus it is very hard to accidentally press a different button unless you don't know what button you're going to press. This alows for more precice and careful presses. However, on the GC controler, the buttons arn't equally placed or sized for that matter. You want to press B but you're all the way at X? Well, get over there! Want to press Y but your thumb is on the C stick? Well you're screwed unless you have lightning reflexes. This is why (I think) that many games use the left analog stick as the main purpose while the right hand uses actions.
And obviuously if you bring FPSs into this and if you want to make an action but the knife button is the O button and your right hand is on the analog stick, then you'd already have to be aiming at the person and hit O as quick as you can so that's where the PS and GC controllers are similar.
But it was a pretty good "essay" though i don't agree with it fully, but i'm sure that my answer wasn't any help either.