Originally Posted by
Terminally Unique 
...I consider anyone who feels inclined to disclose how much "sober time" they have without me asking first, immediately suspect. Their need to per-emptively establish "credibility" in such a way practically proves the state of their own tentative, uncertain, on-the-edge-of-relapse sobriety.
I would caution against reading too much into the simple act of an unprovoked disclosure of sober time. There are reasonable explanations that do not involve "on-the-edge-of-relapse" sobriety, including:
Intentionally establishing credibility to get the attention of the listener. Have you ever found it useful to elucidate the breadth of your knowlege base when attempting to sell your opinions to others?
General insecurity. Simply put, some people are socially awkward and feel the need to wear all manner of credentials on their sleeves.