I agree with almost everything in that article. I have been playing chess for 20+ years. During that time I have spent several months at a time seriously spending all the free time to improve my chess. I have read numerous chess books, many of them multiple times. I have an expert level rating (USCF) now. I wish someone has told me to concentrate on tactics before going after openings or strategies. Nowadays for any new beginner once they learn the rules I tell them to practice tactics.

Learning positional strategies and all the fancy openings from the books was great. But was useless to improve my results when I was beginning. When I analyzed my games with the help of computer, I found 90% of the games were decided because me or the opponent missed a simple tactic which is just 1 or 2 moves deep. If this is the case in your games you should study tactics until you can find all 1-2 move tactics. It sounds easy. But I have seen a number of class A players miss these simple tactics numerous times.

Finally you will understand opening and positional strategies only if you can spot tactics in them. Once you do not find any tactical mistakes in your game you start to play positional chess. You will appreciate making good positional moves when you do not make silly mistakes.