...
Some three - four (?) months ago I tried out Two-Factor Authentication on two
blockchain.info wallets I had, one was using SMS messaging the other was using Google Authenticator. I wanted to try them both and see which worked better for me.
In my case,
neither worked well. Most times I tried to authenticate, it would not "work". And that was a real problem, because I travel (live here in the USA), and wanted to have access to
BTC, even in Peru where I often go.
If I had trouble with Google Authenticator's code numbers expiring too fast here in the USA, I tried to imagine the problems I would have in Peru.......
So, I opened up another wallet and just use the second password option (via Settings then Password from the Home Page), which at least is a partial solution for more security.