New here, but read this site almost daily (post on CelticsGreen...).
I'm not quite ready to throw the towel in on this one yet, as there is still a lot of time between now and the playoffs. JO could conceivably have minor surgery, and/or get a lot more rest. A lot of guys play with bad knees and other body parts. I'll admit it doesn't look good, but trying to remain hopeful - to boot, there's no way we can move him now.
Plus, assuming KG is healthy (if he's not, we're done, JO's health becomes moot), we will have Perk/Shaq at 5, KG/Baby at 4, with JO a possibility at 5/4. Meaning he might not be needed to play every game, much like Doc swapped Powe and Baby back in '08. If JO could play 12-15 games in the last 3 rounds of the playoffs, at maybe 15 mins or so, that just might be enough.
We need ET to come and zap JO's knee....