Even your strongest Android pattern lock is worse than a 3-letter ASCII password
github.com
github.com
Guess I need to go read how that's implemented now.
However if you have debugging disabled and no third party bootloader, you cannot access the filesystem while the phone is locked. So being able to crack some kind of hash is a moot point.
I use it to keep my toddler from messing up my phone while letting him play with it (and hes happy just playing with the pattern)
You can crack it most of the time by just looking at teh screen smudges...
Though maybe that's not the best idea...