[TimG]

Scoring: IMP

1♦-(1♠)-1N-(2♠)
3♦-(P)-3N-all pass

West leads the ♠2 to East's ♠K.
East switches to the ♣4.

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Assume expert opponents. What honor combinations could the ♣4 be from?

If East instead switches to ♣A and continues ♣4, what honor holdings is this likely from?

I guess my questions really amounts to: is there an optimum strategy for east holding ♣AK74? Holding ♣AJ74 (or ♣KJ74)?

[bluecalm]

Optimal strategy for declarer is to always put the T.
Optimal strategy for defender is to always lead low.

Let's try to prove it. EV for declarer if he always put the T is 2/3 wins 1/3 loses (he always wins if RHO has AJxx, KJxx and loses against AKxx). Is there anything defender can do improve his expectation against this fixed strategy of declarer ?
The answer is clearly no because he holds the J 2/3 of the time so no matter how smart he is he will lose 2/3 of the time he is looking at the J.

Now is there anything declarer can do improve his expectation against defender who always lead low ? The answer is again no because if he puts the Q even slight % of the time his expectations will fall below 2/3.

That proves that always leading low and always putting up the T is pair of optimal strategies for both defender and declarer by definition (no player could improve his/her strategy against strategy of other player).
This doesn't mean there aren't more pairs of optimal strategies though.

[MFA]

This theme is great fun. But here east can't really fool around if he has 4 clubs. And hardly even with three. Declarer could well have long clubs, and swallowing partner's stiff honour or H-T doesn't look too clever.

Just play small as declarer.