Okay let me have my shot at it...
The President of The United States of America is the most important (time consuming) job in the world, yet, even he (they) take vacations throughout the year! If they don't take a "break" they would lose their minds and fail to function properly!
If you (anyone) doesn't find time to "get away" every now and then, you will go crazy and exhaust yourselves (probably fall over dead)!
They have off-seasons in sports for a reason (even in sports like golf)... you have to rest and recuperate so you can come back refreshed and ready for the mental and physical toll you have to endure for your jobs! Sure, they get paid millions, but we have billion dollar MACHINES that malfunction if they get overused or not take a break to be serviced ever now and then!
To the people talking about Bird, Jordan, and Kobe... hahaha... I guess you forget about all the extramarital affairs, drinking, gambling, fishing, etc.!
Get real if you are expecting Rondo to be some type of robot or something! He needs time away from the game, both mentally and physically!
I can guarantee he works as hard as most everyone else, you don't get to his level (believe it or not) just based off of God given talents... there are MANY people with amazing physical abilities who will never ever see an NBA court! Seeing as RR is one of the best players alive, should tell you he busts his butt, even if the results don't always (seem to) show it!
No one is perfect at basketball contrary to what you believe... even players like LeRoid, a physical specimen, have struggled at times!
RR improved last season and the ones before it, I expect to see the same type of improvements this season, the guy is only like 26 and easily one of the best alive!
Give him a break!