Hey guys,

I recently was listening to Alestorm and was wondering how the heck they make their music so... piratey? I really want to write a whole composition as a gag in pirate style but don't know how they're doing it!

Quote by SlackerBabbath
My ideal woman would be a grossly overweight woman who would happy go jogging, come home all sweaty and let me put my dick under her armpit while she shuffles a pack of cards.

Stay classy, pit.
Pirate music is usually in 3/4 or 6/8 timing, so, that's a place to start. The musical melody always has a rocking-of-the-ship kinda of feel.

Like, OneTwoThree, threetwoOne, Kind of back and forth

Idk, I think Pirate metal is a laughing matter so, I'm the wrong person to ask
How many guitar players does it take to change a light bulb?

Twelve. One to change the bulb and eleven to say they could do it better.

in terms of scales it's pretty simple minor pentatonic / aeolian stuff, the pirate-y fee; just comes from the instrumentation / feel / lyrics
Instead of impersonating a band impersonating a genre, why don't you listen to some of the original genre's songs? What I'm saying is learn some sea-shanties on the guitar, add distortion after if you wish.

As mentioned above it just sounds like straight minor stuff in that link you gave. The pirate feel comes from the timing, arrangement and instrumentation of the piece.
And no, Guitar Hero will not help. Even on expert. Really.