no way is the tbpr 4 months out of date, its weeks not months.
I wonder what you mean by real pr. Perhaps you mean pure raw page rank as it was in its very early days in which case i think you mean its not old the old formula for pr. Or maybe you mean its nothing to with the pr that is applied to your page for ranking purposes, well i would disagree, its just not the same figure for all pages because as was said, its indicative of other factors when it hits the toolbar.
Yes its goes grey and normal again because the signals they were reacting to have changed which might not even be onsite, or their own parameters have changed, or you was on a threshold that can easily shift either side at any one moment, and tbpr is a snapshot.
TBPR is not broken at all. The backlinks is not broken either, its been de seo-usefulised.
Thank you for your facts. :)