A few takeaways:
- When attacking,
- Always try to involve all your pieces (cf. 21.Re1!!)
- Try not to exchange your attacking pieces unless there is a clear gain in sight (True that 21.Nxh8+ grabs the exchange but White still remains a piece down with a dying initiative)
- Even if the attack is not going your way, keep trying to find resources and counter chances; even after Nxh8+, Kavalek probably misses a draw at some point in the game (28. Ba5!? instead of 28.Qf3)
- When defending,
- Sit tight and calculate variations!
- Don't be afraid to make "ugly" moves (24...Qh7; 28...Qh8) as long as they are backed up by your calculations
- Be patient and your time will come! (30...Qxc4+)
We have to credit L. Kavalek for his inventiveness and courage to play such a bold move, what a pity that he was not able to follow up with the right idea!