OK, I have done a pile of research on this and developed a theory. I don't think the throw out bearing itself is the issue but is actually a symptom. The root cause is actually bent or off center release forks. If the fork is not perfectly aligned or is even slightly twisted it can put lateral pressure on the bearing which of course is going to produce premature wear and failure. It would not have to be that far out to cause an issue and could sneak past a visual inspection pretty easily.
Subaru uses a stamped part for this fork (above) and I know that historically (at the one plant I work at) stamped parts such as this have a very spotty quality record since it is very easy to miss small imperfections or errors in specs.
Through the course of my research I found many different cases of failure of these forks on Subaru products right up to them actually breaking (in fact somebody on here broke one and although I am not positive @
ichitaka05 's name comes to mind). Now obviously a cracked or broken fork is the extreme and very easy to spot but an even slightly bent or twisted fork could put some extreme pressure on the bearing and cause it to heat up when it is spinning.
Added to the evidence is the fact that many of the guys that have had issues initially just had the forks lubed when they went in. Although the lube seemed to help for a while eventually the bearing failed anyway. This would lead me to believe that the act of lubing at least temporarily centered the fork and took the sideways/angled pressure off the bearing.
Well, there you have it guys that is my theory. I guess the point of my post is to look beyond the direct result and try to find the root cause. If you have bearing issues it may be worth while changing out the fork as well since a bad batch of forks could easily explain why so many have issue but loads of others don't.
P.S. Or I could be talking out of my ass on the subject and am totally wrong.