yeah, i guess it would have just been around in time for loveless.
i'm only going on what i saw My Vitriol using live, i guess you've heard of them if you like MBV, anyway, they have the whole chord gliding thing going on too.
some of the sounds on loveless and isn't anything i think are as simple as depressing the tremelo and strumming as you release it. Andy Summers uses this technique too but obviously it sounds loads different seeing as his guitar is clean with a little chorus, and MBV is drenched in delay and overdrive.
in fact, i tried this technique on a song i was messing about with ages ago and it did sound pretty convincing, just needs loads of reverb, overdrive and delay.
