if his chips were not overheating. the only way cleanup of excess paste helps is the paste has some electrical conductivity.
Could be it does just a little. we would need a very good ohms meter and someone willing to open his s-3 clean off the oem paste and see just how conductive it is on an electrical level.
Could be. I have an absolute dog of a s3 that's has all but One chip on a board disabled. I'll crack it open and try replacing the thermal paste.
Let you guys know