On the viability of S3's, I did not say they were no longer viable, in any case, there's the argument for S1 to S5 kits in the same suggestion (but of-course you conveniently skimmed over that).
I spoke with yoshi (by email) and they are considering an s1-s5 upgrade kit but not until they get some feedback on batch 1. Upgrade kits are not for inexperienced people and poor thermal paste application or nicking something with a screw driver could result in a few loud and disgruntled buyers who can't RMA a diy product that they damaged by improper installation.
My guess is upgrade kits will either have no warranty or be provided only in bulk packs of 5+ so that it isn't being sold to people incapable of correct use.
That sounds OK and thanks for taking the time to speak with the big man himself.
I completely understand that position, aka no warranty and mostly only being available in packs. But I think there is also market for bare S3 boards' packs, and I am sure they've also looked at that.
All round, good news and thanks for conveying it on Xmas day. Merry XMAS!