Off with your head......
Now on a semi-serious note, basically messing with your rig and inching that last bit mid month is a terrrible thing to do. It takes 12 hours to do a job. Lets says you move from 4.2ghz to 4.3ghz and gain 30 seconds per %. That equates to 100 seconds per day(roughly), which means roughly you would gain 3000 seconds per month...thats 50 extra minutes of folding. But if you up it and fail just one job out you lost 12 hours of folding. Its just not worth it. If your stable that last 0.1ghz isn't going to help your team if you have a problem.
Now if your in the boat where your in 4th and have it locked, nothing you do will change that...then that would be the time to find your best overclock and lock it in before the new month.(let me assure you this was a lesson I had to learn over many months and the hard way)