I'm pretty sure none of these were ever "totally legal" and if the authorities wanted to fuck you they could. If they were totally legal all the big supp companies would have sold them but they didn't. Even the companies selling them were selling them under different labels/companies. bb.com got a lot of heat for these supposedly legal compounds, Patrick Arnold was fucked over for something many other were doing as well etc.
Yeah, back in the day around 1997 -98, Vida's book was known, and the grey area was wondered about. Kneller, Arnold, Duchaine, and a few others were batting around the idea of importing and marketing some of the harder compounds, and it was finally decided against because everyone figured that it would definitely cause the some heavy legal crackdowns. It wasn't until Syntrax had that nice long run with relatively little trouble, that more people had the confidence to enter the game, at least in my estimation.