I've been away intermittently, and realize I'd been holding this on my desk while waiting to check some references.
Max's comments in the 9e Colloq. were much more influential than one could guess today. I was surprised that he had never
published them more formally than that.
Besides this bent, you may recall that he was very much engaged with phage inhibition from without, and even demurred at the
idea of particle-recombination in his experiments with Al Hershey (CSH 1946) in favor of some more revolutionary mode of information
I would guess he has always regretted not finding some deeper principle for biology that would correspond to indeterminacy