it might be seconds... if you use a sledgehammer ;-)

It is a close relative to "rubberhose cryptoanalysis". Although an extreme example, it is a good example of that security is a system, and the simple weakest link determines the strength of the whole system.

That's why there's no reason concentrate on the "perfect" stuff ("two timers are certainly running out of sync, especially when we take the LSB five times"), if there are ways around it ("it's possible to get one of the timers stuck with zapping the whole stuff with a strong electrostatic discharge", for example).

JW