Ahh…ya, that doesn’t seem right. Perhaps there is a use case, where this makes sense.
I suppose a work-around is to remove the formatting that is based on invalid, and do your own validation of the value. I actually did something like that for password creation using the new plugin from our buddies at AirDev: [New plugin] Instant Text. I use a standard text box for the user to create their password, and pipe it over to the instant text element. From there, I use some regex extracts to determine in real when each part of the password policy has been met. Depending on you validation needs, maybe that would help?