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Could you please add an explanation about this issue: After W invades 3-3 (B has only 4-4), B plays 2-2 as a defense in order to keep the corner (no discussion why this is good or bad, just assuming B wants to defend.) Assuming no other B or W stones around.
- Can W survive? How? - And more general, assuming not further stones around: Can B kill W's 3-3 invasion in principle, assuming perfect play of B?
That isn't a defence but just a bad move. White just don't have to get obsessed with killing the 22 stone, but extend to the outside on one of the 3-4 points.
Assuming no other stones around, Black cannot kill the 33 invasion. Black has no better move than blocking and allowing white to live.
For your specific question, see 33PointInvasion/Discussion. --Hyperpape
Thanks a lot for the helpful clarifications.