To Round the Back, or Not?

This is my rest day. I will take my rest day. I will not do a WOD; at most, I will make a date with the foam roller and 'work out the kinks'. But in the meantime, I would like to pose a question: When attempting a deadlift PR (personal record), do you sacrifice less-than-perfect form, and allow a rounded back? Or, do you terminate the lift once you determine that your poor form has compromised the legitimacy of the lift?

It is my belief that if you have developed sound core strength, and have consistently trained major lifts, such as the deadlift, front squat, overhead squat, clean, and snatch, then you have the credibility to 'compromise' a little bit of a rounded back when attempting a one-rep maximum deadlift. If you are brand new to the lift or your body is not conditioned to support a maximum load, then of course, a maximum lift is out of the question - especially when good form is compromised.

Check out one of my deadlifts during the second WOD of the 2009 CrossFit Games (lower left-hand corner):