Sollozo had a foolproof plan.
Kill Luca.
Execute Don, kidnap Tom simultaneously.Get permission from other families beforehand.

Get police captain to pull Don's security at the hospital and plan another hit.

The Don surviving the hit..and Mike ACTUALLY shooting Sollozo and a police captain were actually impossible to predict or factor.



If you read the account of the meeting again, even Tom noted that Sollozo radiated power and force..."even more than Don Vito"

In fact..for some reason..Sollozo's play reminds me of the decision that young Vito made to NOT pay Fannuci.

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The Don himself, in Sonny's shoes with the situation being what it was might have taken the same deal. In fact, with Sonny dead and Mike on the lam, he in fact did take the deal, more or less.