> So if I forget to uncheck the LVM install checkbox on my dual-boot PC, and I need to shrink the Windows partition, I'm screwed.
I understand you are "screwed" only because you cannot live without gparted.
Dual-boot is where I found LVM really, really kicks ass.
Realize you allocated too much space for Windows. Shrunk Windows and re-allocate what you just got to ANY other partition ANYWHERE on the system without moving anything. Simply cannot be done without an indirection layer like LVM.