I dont think through just hard work alone you can reach GM status. If you dont have some talent/ability you can only reach a certain level through work alone and I think that level will be below GM level. Fischer was asked about this, he was asked could a person become a "great" player through hard work alone and he said no , he didnt believe so. Unfortunately , neither the questioner, nor Fischer, defined "great".
Fischer said that a player with no real talent could be good, but not great. He expounded on this by saying that "a number of the top players, I don't think are that talented, they just work like dogs", so Fischer clearly believed that GM level was obtainable through hard work alone.
k, could not find the Lasker book - but I did come across some websites that may be of interest, if all the OP is looking for is a structure to learn/improve with :
http://www.iamcoach.com/chess/chessexam.htm - this site has two self published self assesment books by a GM out of Pennsylvannia - I plan to check this out as soon as I can, myself.
http://www.chessmasterschool.com/ - I stumbled across this in my search for a chess course; the OP may actually benefit more from this than I can. Claims to give you a structured learning path to mastership in 13 months; they say you will have all of the information you need to reach your goal...
The OP may also find the two middlegame books I have to be of interest (I am too weak to use them yet - but I am not giving them away or selling them...)
"Practical Middlegame Tips" by Edgar Mednis
"Chess Middlegames : Essential Knowledge" by Yuri Averbakh
As for me ? Tactics, tactics, tactics ! Will likely be a couple of months minimum before I am able to check out the two links at the top. At any rate, this is a really cool thread - lots of nice info - hopefully I added to the discussion !