Don't use random thread to ask your question if it's unrelatead the the subject.
you even chose an old thread from 2 month ago.
To answer your question:
Everybody is doing this! This is the correct way to do it, so yes, it's possible.
The drive has to be FAT32 with 32k/cluster, formated with only one partition.
if you have multiple partitions, you need to put Gamecube games on the first partition, wii games can be on any.