[dom0]

No, not at all. A raised SNR can be overcome in almost all circumstances by making more measurements, i.e. correlation, since noise is not correlated, it is removed. For the same reason random delays don't help against timing attacks.

[Drdrdrq]

Curious: how about generating noise which is correlated to signal and actively tries to modify output to some "random" noise?

[Cyph0n]

That's how DPA works as far as I understand.

[Ferofluid]

Not if you calculate keys nonstop, then have another machine pick from a huge list later.

[tinus_hn]

Perhaps you could quantize the level.