I have my answer. It took me 5 seconds to figure out the
answer, and another few minutes to write up my analysis.
I don't want to spoil it for others, so I will wait a bit
before posting my analysis. To keep me from cheating,
here is the sha1sum of the current (initial) version of
my writeup:
090bb621c28d7301492a18cf7b7a2a4cedc26d04