kano said that bitmain is using asicboost, which everybody thought was just patented software.
...
Yep, as per the document I pointed out in their S9 thread:
https://bitcointalk.org/index.php?topic=1493601.msg15634328#msg15634328and also the stratum change they made to enable it in the miner, since it works a little differently when talking to the pool,
that broke S9 <-> ckpool initially (until they fixed it)
However, if they were 'actually' using it, we'd see blocks with the block version numbers matching the change.
I'm not sure how many such blocks exist.