Hmmm every time I've encountered LSD blotters at least, the taste has been slightly bitter. Could this be down to the inks in the blotter paper as oppose to the LSD itself? Of all the 60/70 times I've encountered LSD here in the UK, I'm pretty damn sure it was as advertised, apart from one time when the blotters were bunk. The only thing that varied for me, and considerably so, was the dosage per blotter...some were nice for a buzz and a giggle with sensory enhancement; others produced a very deep psychedelic experience. Alexander Shulgin himself said that contrary to popular opinion, pure LSD is not tasteless and is in fact "slightly bitter" (kind of trust his opinion on this). Think you may need a good dose of pure stuff to detect this though.

Does anyone else get a strong metallic taste while actually on LSD? Quite distinctive to me, tastes like...electricity or something. Interesting you describe noticing something immediately on taking it on your tongue. I remember hearing the same thing regarding the old "thumb print" acid tests, if these did actually take place.