Hey there everyone. I've been around these forums for about 5 or 6 years, but this is my first post.
I've watched almost Celtics game in the Rondo era. This year he has been at his worst by far in my opinion. It's not just his shooting that's different. It's his ability to create offense for himself and as such he's averaging a career worst 8ppg.
I know most people will argue that his assist and rebound numbers are great and they are, but that doesn't change the fact that he's personally struggling. The odd thing is that I don't think Rondo has changed as a player, before his ACL tear he averaged almost 14ppg which would have been a career best and then his first year in the post KG/PP era he averaged 11 points per game coming off that ACL tear(which is a small drop off in the bigger scheme of things, but it's relevant). Now another year removed from the surgery his scoring has gotten even worse.
So why is this happening? Assuming rondo isn't just getting worse(which I don't think he is) then something else is causing the problem. I think the problem is team spacing, mostly in regard to how our Centers open up the floor for Rondo driving lanes. In the last few years with KG he was playing exclusively the center spot, but he almost never went back to the basket. Instead it was all pick in pop for a mid range jumper. KG's amazing mid range jumper would cause the shot blocker to come all the way out of the paint to contest. Which meant rondo could get to work either with an assist to KG or by taking it to the basket when the opposing center stepped out.
Last year we had some of the same dynamic because Sully had really developed that same mid range shot that KG had. Which again opened up the paint for Rondo, but now all that's changed. Sully started the transition to the 3 point line last year and at the same time rondo's scoring started to dip. Now Sullinger almost only goes to the 3 point line or posts up. Now he is shooting around 36% for the season, which isn't bad for a big fella, but it changes the dynamic that allows Rondo to get to the rim, because it's not on pick and pops that Sully is getting open for those threes.
In summary: Tone down on the Sully 3's by putting him in mid range pick and pops with Rondo and you'll see an increase in Rondo's ability to work and have options that can help win late in the game either off a pass for a Sully mid-range or a drive to the basket with sully as a decoy. Of course in that situation you can spread the floor with JG, KO, and Bradley as well giving rondo even more options past the first two.

That's all folks!