That is true, but the variability is just huge. Nola was also a "low ceiling, high floor" guy and now he is looking like the ceiling is much, much higher than anyone realized. He is quickly turning into a #1 and a top 10-15 (at least) pitcher in the league, and is still on the "getting better" side of age.
Picks are picks, and in baseball the odds are just not good. I agree that going a little higher on ceiling to try and get a premium player is a good plan with a high pick, but I wonder how many guys that are multiple All-Stars actually were top 10 picks and how many of those top 10 picks really just didnt work out. Our last few have been pretty awful it appears, but Nola alone might make the last few years look OK.