I (black) decided to play diagonal fuseki so as to
1) Make enclosure by 4
2) And make large low extension by 6 ( however white cracked the plan)
A. Is it viably strategy?
B. What is the best response to his extension?

Also look at moves 21 - 41.
1)How can I punish H16 being too far?
2)My plan here was to sacrifice stones to build thickness. What are mistakes in terms of strategy and tactics

1. At our level diagonal fuseki are ok. But I think better players avoid it because it tends to erase the profit of the first move. Komi is then a bigger problem.
2. leaves a nice spot for you at R12. But for now I like ur . I would have played at K3 because it combines two purposes: an extension and a pincer. I would play at R8 or maybe N4. The cut at P4 will remain a problem for him.
3. I dont think G16 is too far away. at C16 is better shape. Dont give away cutting points for free!
4. Playing the armpit ( ) usually is bad. Also here I think. If you want to attack then first you have to defend your 21-25 stones. But probably C13 is best because when you are weak attaching is often best. If then W hanes at C12 I would crosscut at D12. Because you have stones nearby you gain more.
5 B45 is a never again move. Don't hope he won't see the ladder.

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