It's probably be a lot of work so not a suggestion, just a thought experiment.
Start with a lump sum like you have, $1000 something. Buy $1000 of Bitcoin and start him on $1000 of cash.
Every time he makes a prediction about Bitcoin, plot the resulting loss (win). On top of that, plot how much money he made from that post.
So if he makes a shit prediction and his Bitcoin 'fund' loses $200 then his running total for Bitcoin is $800. On the other hand, his post made $300 so his 'cash' fund is now $1300. Plot both on the same chart.
Don't know what it'll prove though, nothing you don't already know. Follow his advice and lose money while he profits just from writing it.