|2 people marked this as a favorite.|
I don't think a weapon doubles in size the way you are thinking it does.
A greatsword, historically is somewhere in the 5 to 7 foot range (with some outliers).
As I understand it, a medium sized character roughly fits in a 5 foot cube, a large roughly fits in a 10 foot cube, a huge roughly fits in a 15 foot cube, and a gargantuan roughly fits in a 20 foot cube.
So a greatsword isn't likely doubling in length every time you change a size category.
A greatsword for a gargantuan character is probably around 20 to 28 feet long, not 48.
Now, greatswords, if Paizo wanted to be realistic about it, should probably have reach, and larger weapons should probably deal extra damage, but my guess is that the game wouldn't be balanced in that case, so instead of modifying the rules to make it balanced, we just have weird instances like this that break immersion.