Well, thanks for scaring the c**p out of me! Makes me want to pop my valve cover ASAP!
I respectfully disagree on the oil weight being a factor. I've run my engine exclusively on 5w-20 (and a blip of 0w-20) for 160k with no issue (knock on wood). There are far too many k24's on the road that have done the same, into the millions and millions of miles. If the viscosity were and issue we would have heard much more on this galling problem and Honda would have issued a TSB. That is my opinion.
Consider re-posting your valvetrain pics in the General Automotive Section, guys eat that stuff up.