You scroll with the arrow keys. The "obscure commands" (ctrl-p and ctrl-n) are to get to the Previous and Next commands typed and are more or less universal in unix command line systems.
I've used Unix a lot and I've never used Ctrl-P or Ctrl-N for previous/next. Ask 99% of people what those do and they'll either have no idea or say Print, New. Ask 99.999999% of people how you scroll in gdb and none of them will guess Ctrl-P/Ctrl-N. It's shit.