Thin Tummy exercise (from Thinking Mans' Guide to Ab Training)

Hi. I’ve got a question regarding the thin tummy exercise, that’s part of the Thinking Man’s Guide to Ab Training. Would it be beneficial to do this exercise anytime/anyplace? For example, if I’m sitting in the car, or at my desk, for example, and I perform the Thin Tummy periodically, would that be overkill? (meaning, working my abs TOO much?) My goal (like everybody else’s), is to get a good midsection going, and I thought if I could practice doing thin tummy exercises throughout the day, that would help me achieve my goals faster. I appreciate anybody’s comments and thank you for your time.

Yes, you can do them whenever, wherever.