I've done 1000 and 1500 ug doses and don't think I could differentiate between the two. Personally I see no reason to go above 600-750 mics - pretty much at plateau by then.
As far as this whole "thumb printing" business goes, as far as I can see it only comes from chinacat and a few of his fluffers. He has hundreds of stories, lotsa contradictions ("Only a sacred few were allowed the thumb print ritual" then on other occasions he's known literally hundreds of people who safely survived a thumb print.)
And then some of it just nonsense. Like the Oakland story. He laid 50000 hits in front of a guy he did not know well. Then was going to give some crystal to his buddy to take home so he just dumped it out on the table. Then strange guy thumb printed himself from the pile and began to freak. Chinacat freaked and threw the trays, crystal, and 50000 hits outta the hotel window because he was afraid someone would call the cops?
First of all, lay 50000 hits in front of strange person? Right. This guy supposedly did this shit for years and stayed outta jail. Then give some crystal to your buddy - not in another vial, but dump it out on a hotel room table. Then do what? Scrape it into something else with your credit card? Then toss all the shit? Uhh. Right. Assuming any part of this really happened, why not just grab the trays, the sheets, the vials in 5 minutes, put them in your backpack, leave someone to babysit, and split immediately with goods and take a cab to another hotel?
And all these "close calls" - always a comment that he made it through because of the "protective kind karma of the thumb print family".
Get real folks. Use some common sense. I doubt anyone even does the kind of utterly stupid shit, much less does it for years without getting busted that this claims to have done.
Personally I've been going to Dead family shows for almost three decades. The last time I saw a show was three days ago - taped Phil Lesh up in Philly.
I've known hundreds of deadheads, still meeting new ones. Don't know about the Rainbow Family , but I am the Dead Family - the real family about going to shows, taping the shows, lotsa of other things that make us Family, but not thumb printing LSD. In all my years, and all my many acquaintances, I never met anyone who had done a thumb print, or for that matter anyone who had every heard of anyone who had done a thumb print.
If you think it is cool or glamorous or exciting and you really just want yourself to believe it;s true, hey be a heady kind believer in the kind heady protective karma of the holy thumbprinted ones whose counts apparently range from the sacred few to hundreds depending on who you ask, no wait depending on the story the same person happens to be telling at the time. BY all means, enjoy the story.
My own opinion? The "thumb print" is a total crock of shit.