[cosmolev]

Why should it be constant-time, by the way? Wouldn't random-time suffice?

[DexesTTP]

There's a good chunk of the article about that. "Constant-tile" is a bit of a misnomer, "secret-independent resource consumption" is a better way to say it. If you just add a "sleep(rand)" or equivalent then you can still break the secret using statistics or sidechannel attacks.