IMO, who the hell would waste their time lacing acid? It's such a powerful drug that anything that it is laced with would be drowned out by the LSD. Besides, unlaced acid looks exactly like laced acid- a little square of paper or a clear liquid. And, acid is cheap to produce. That's why a hit only costs a few bucks. So, why would a chemist bother buying/making another chemical to cut the supply of acid?

This whole concept has its roots in the great strichnine (sp?) debate, which I also think is bullshit.