Answering a student's question

Q:
Could I ask you about this position (Danis v Skora Corr 1977)?

In this variation of Black's 21-st move, White has just played 25. g3! Why has the annotator has given this an exclamation mark? What is the idea behind this move( if 25.Kc7 then 26.h4 h6 and still W cannot get control of f4 for his Queen)?This plan is slow and will fail for White.

A:

Here it just looks like some missplelling or a typo. I guess that the move was Qg3!!  there,  with irrefutable kingatack, and not g3. Also White is a piece down here, and g3 is just useless there, it looks like he had sacrificed a piece previously somewhere in order to obtain this opportunity of King-attack with Qg3. A nice position and example, indeed☺