After giving it some more thought, I would like to revisit this:
Well, this result demonstrates that only the outputs of that puzzle transaction were searched by whoever did that, which only mildly surprises me.
The alleged mode of search of whoever did the search for the PKs in the puzzle transaction was discussed
in
https://bitcointalk.org/index.php?topic=1573035.msg16348760#msg16348760 ff.
between you and donGeilo
We have found #45 (
https://bitcointalk.org/index.php?topic=1573035.msg16430637#msg16430637), but have not yet found #46 (
https://blockchain.info/address/1F3JRMWudBaj48EhwcHDdpeuy2jwACNxjP).
The fact, that we have found 1PVwqUXrD5phy6gWrqJUrhpsPiBkTnftGg in-between, which a) pre-dates the puzzle transaction, b) seems to be there
before (in terms of key value) 1F3JRMWudBaj48EhwcHDdpeuy2jwACNxjP indicates, that whoever searched for the puzzle funds, did not perform a search such as both you and donGeilo assumed. Which - honestly - should take the mildness from your surprise.
Only explanation I have (which is consistent with the observations so far) , would be that the searches were performed backwards (i.e. for #46 starting at bit47, then decrementing PK values) and rest of the search space is skipped when puzzle transaction is found (starting again at bit48 for search of #47). IMHO this is the only way how 1PVwqUXrD5phy6gWrqJUrhpsPiBkTnftGg could have remained unseen in that search.
Alternative explanation could be that 1PVwqUXrD5phy6gWrqJUrhpsPiBkTnftGg was seen, but not bothered to touch. Not sure how probable that is.
Rico