I only ever used clearblocks once when I first discovered this modpack. I did it on a test world so I could learn how the oregen actually works. I never tried the countblocks command. If you try it, let us know how that works for you.
EDIT: But I suspect that it would work... a bit cheaty imho... but if your goal is to find the tin without the grind of searching, it should work.
Okay, I might not need to try it, I went on an exploratory trip to find some caves or more tin, and found a nice Tin vein in one of them. Hopefully it'll be enough to get past the Steam Era and into using an Ender Quarry to mine some more tin up from veins or wherever it's hiding. I have got to say, though, it is a hard resource to locate.
In any case, I now have some tin should I need to try locating it.
Quick question, Tetrahedrite is easy enough to find does anyone smelt it directly to copper if they need it? I've got plenty of copper locations I can get the raw ore from so hopefully won't need to.
Cheers ...
BrickVoid