[JustResign]

Either I'm missing something big, or this site is.

It assumes you can rent this capacity via NiceHash, but the whole point of a 51% attack is to run _different code_ on the majority of nodes.

Surely NiceHash would rent you capacity running the vanilla e.g. Ethereum code, rather than your fork?

To assume otherwise basically makes NiceHash remote code execution as a service.

[wmf]

You're missing some details about how mining works. "Miners" don't produce blocks; they just do hashing; the mining pools generate the blocks. When you rent mining capacity from NiceHash you can point it to your own pool (full node) to do whatever you want.