We are preparing options to force delays on Bitcoins (rule set depending on aggregated 24 hours transfer amount - option configurable from the user) and emergency account lockout (that would automatically cancel any delayed transfer).
No!! You can't do this.
This(Instant Bitcoins Withdraw) is the only thing that keep you different from FRB banks.If you do this, i will never trust you again. Instant Withdraw should be the STANDARD of Bitcoin Banks.Sounds like this would be a user configurable option. Mandating some form of two factor authentication for "large" transactions would be reasonable.