Help spotting tactics in this position

Sure, ideally you do it in real games too.

That's exactly what went through my mind regarding Qh6, it was even subconscious. First step in blunder check is about avoiding moving a piece towards a square where it will be captured on the next move. How often do you calculate moves that involves placing a queen right in front of enemy pawns? Or developing a piece where it will be lost on the next move? I naturally don't even consider those moves, it would make me exhausted to consider them during a full game.

But in this case, Qh6 is a threat in deed. I guess i need to sharpen my alarm bell for when it's time to look for this kinds of tactics/threats. Having several active pieces & being in a sharp position is one of those alarm bells i suppose.

It might help if you approached the problem from the opposite direction.

Instead of looking at the position in front of you and wondering "How do I break through and mate the enemy King?", you might try closing your eyes and thinking "I have succeeded in mating the enemy King!"

Then ask yourself "How did I do it?". In the position you gave in the OP (Original Post), the most obvious potential mate is a Rook+Bishop mate, with the Rook mating along the g-file while the Bishop prevents the enemy King from fleeing to h8. All this requires is that the two g-Pawns (your Pawn on g5 and Black's Pawn on g7) should disappear.

... and at this point, 1. Qh6 gxh6 2. gxh6 mate should suggest itself.

What?

You can only say that because it's an easy puzzle for you. Pre-calculation, the most obvious mate to me is something like Rg3-h3-Qxh7 because the h file is the major open line.

In fact if black's b pawn didn't exist, that maneuver is probably just instantly winning.

In games I try to do it all the time, but only moves that makes threats.

More often than instantly winning what happens is you notice "this threat almost works, but his knight is a good defender" so then you switch to a candidate move that works to remove the opponent's knight, and calculate that a little.

Noticing latent tactics is super important. So yeah, I try calculate moves like that all the time... of course even the best players in the world miss tactical shots because they're preoccupied thinking about strategic stuff. The sharper the position the more alert players tend to be.

As for your saying it would be tiring... yes, this habit is very tedious to build.

It's an easy puzzle for me because I know my model mates.

Good players don't usually analyze move-by-move... I-go-here, he-goes-there. They analyze in conceptual "chunks".

Knowing your model mates allows you to look at a position on a higher tactical granularity level, just like knowing the typical central Pawn formations (Jump formation, Wedge formation, Ram formation, Boleslavsky Wall, Botvinnik formation, etc) allows you to look at a position on a higher strategic granularity level.

That's true, knowing typical mating patterns would help a lot in solving this puzzle.

Like I said, I used to teach this stuff at chess clubs. Decades ago.

Oh, but I meant to say also, it's tedious and tiring, but once you've built the habit it takes a lot less energy. In the beginning it's probably something like 80% of your energy during a game is just calculating forcing moves, but then after 6 or 12 months of practice it's significantly easier.

This is what I said. Once you solve around 1000 basic tactics you start seeing the difficult ones as well since they are based on a combination of simple patterns. 

Yeah, and I think I saw earlier in the topic you recommended Chandler's book, and that's of course good.

I just don't like it when people say to lower rated players "well this is obvious" when they can only say that due to their experience.