If he is a rationalist, I would expect that he has a good grasp of when it is socially pragmatic to shake hands, and when he can operate under Crocker's rules and request not to shake hands. I also expect that he is smart enough to have an antibacterial wipe in his pocket to use after shaking hands (but not use it until he is out of sight in the gardens).
What do Crocker's rules have to do with this? Also, it seems carrying antibacterial wipe to use after shaking hands is excessive. The chance that he'll suffer serious health problems from infection by handshake is so small that I doubt even the time taken for all these efforts is worth it.
If it's worth saying, but not worth its own post (even in Discussion), then it goes here.
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