Either the 2FA is enforced solely by code in Steem Pressure, in which case it's a placebo which adds no security at all (but is a lot of work to implement), or it requires a secret on my server, which is even less secure. :P

As to Steem Power, it's as safe as your account is. If someone stole your owner key, you'd be sunk, but at least it would take them 2 years to sell it all. :P