I don't think 16x was ever really possible..

I just wanna say,
Any infantry unit that can change movement speed can have a super duper walking speed under the right conditions. I'm sure youve all seen it.
Throw two units running at eachother (with increased speeds) and then they run side by side perpendicularily (Sp? I just made up a word?) I dont know what the word is, but they change their direction by 90 degrees. They run side by side, super super fast.
Units like Zealots, Zerglings, Lurks(but only for about 3 building squares), Hydralisks, Firebats, and rines (maybe others?) are good examples of this.

Yeah, we've seen it.
And the effect is of no use.
It's just an annoying glitch.