I'm beginning the process of tying my flies for next season, which
will be my 2nd season of fly fishing. One place I'm planning on
fishing for Rainbow & Brown trout next season has two flies on the
"recommended list" that look kind of similar to my newbie eyes:

Cracklebacks: http://www.flyanglersonline.com/flyt...80502fotw.html

Griffith's Gnats: http://hipwader.com/2004/tying-griffiths-gnat-pattern

Are these different enough to make it worth my while to tie both? My
gut feeling is that this is probably a real stupid question, but hey,
how do you learn if you don't ask...