Why is "Tina" Slang For Crystal Meth?

Does anyone have a clue why the hell "Tina" is slang for crystal meth? I've Googled it, and all I can find that even remotely explains it is this entry:
"Tina Or Teena - name derives from the fact that meth is commonly bought in sixteenths of an ounce packages (aka "baggies") "

THIS MAKES NO SENSE. It only comes up because my company's name is This Is Not Art! Productions, and sometimes I refer to it as Tina, as in "Tina's picking up dinner" or "Tina just bought a new printer." And my company's site is really pathetic (especially considering what I do and who I've done it for). And when I mentioned to my friend Liz that I'm finally building a proper site for Tina, she was confused - she thought I was building a site dedicated to FAQs about crystal meth.

So really, does anyone have any clue why this name stuck? I mean... It makes no sense whatsoever.