It almost sounds convincing since OP mention link about how to calculate the Z and throw some jargon. The worst part is 1 people got scammed according to satoshidisc statistic.
Yeah, these signatures aren't reusing R at all, or it would be pretty obvious.
Yeah. That's actually what I thought before investigating further. Any weak keys would've been swiped by the many bots that search for vulnerable keys by now. I believe there's actually quite a few of them just sitting around and monitoring the mempool.
It reminds me of bot which actively monitor brainwallet with common keyword or quote (
https://bitcointalk.org/index.php?topic=4768828.0)