Probably trills (not sure about the name) while sliding the detached whammy arm up the string. They seem to do that trick quite often.
Yeah it sounds like either that or sometype of slide with a continous combo of trills.....sounds kinda cool...have you tried looking up the tab or trying to find a live performance on youtube....

Wonder how you would do that on guitar hero? HAHAHAHA!!!!
Fender 70s Ri Strats w/various Dimarzios
Modded 1982 Marshall JCM800 2203

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Check out randy dobsons underground ,tell me what you think