Don't think Monroe really does anything for the Cs outside of use up cap space.
Besides score, rebound, and pass.
Don't think he fits the way the C's play. And he's not a great defender either.
He's much improved this year. He was actually very good defensively in the playoffs.
He's a good passer and addresses the rebounding need and would be the best post scorer on the team. I'd gladly take him.
Agreed, he would fit in to the offense quite well. His defense is possibly suspect, but couldn't be worse than Amir/Zeller/KO.
Amir and Kelly are excellent defenders. I rank G-Mon a level below them, but still a plus.
It's been my experience that mostly fans don't see defense, especially team defense; instead they go by fleeting impressions, overrate individual defense or blocked shots or steals - or, frankly, they simply repeat what they happen to have heard. I guess it's not surprising that the casual observer would not see the defense, since the pull is toward looking at the ball.
Not intending to insult anyone.
Out of curiosity, what's an "excellent defender" do under your definition?
"My" definition is just the bottom line: what a player contributes to the other team not scoring, sum total, in whatever ways he does it. The team defense at the NBA level is more important than the individual defense, so there are three main things: where the opponent takes shots; whether the opponent gets an open shot; and whether the ball can get to the player that an opponent wants to take the shot.
So how does an individual impact those team goals? Multiple ways, of course, but there are some telling measures for each of those, and as it turns out Kelly Olynyk is contributing in all three areas. Details follow.
KO ... frequently missed rotations, picked up fouls trying to take charges or pick steals...
You may remember Brad Stevens expressing his frustration in November and December about his guys' defense, saying that he just wanted somebody who can get in front of an opponent; this led directly to Jerebko getting some starts, since despite his limitations he at least will reliably body up. We saw that with Kelly, too - he made it a priority to get in front of drivers, and with Isaiah's struggles keeping in front there was plenty of need for bigs to help in the lane. If I'm a coach, frankly, I'd rather see some fouls that send a message. But more than that, I'd rather see perimeter players keeping their assignments out of the lane so that bigs don't have to risk fouling.
What you don't mention is that Kelly was one of the league
leaders in charges drawn (16th among players who played at least 50 games) - in 21 minutes of action. Marcus Smart was 8th, by the way, but if you control for minutes played, Olynyk and Smart are tied.
The trouble with seat-of-the-pants defensive observations is that they lack context, are subject to recency effects, and are unduly weighted by what you already expect of a player.
You claim that Kelly "frequently missed rotations". That sounds concrete at first, but it's not possible to evaluate. Compared to what? To whom?
A real-world way of looking at that: Olynyk was second on the team in contested shots, after Horford, and that included a fair amount of closing out to the three-point line, since he's more mobile than Al. If you control for minutes played, Olynyk was tops on the team, despite all the ground he's got to cover, and in fact if you control for minutes, Olynyk was tops on the team in 3-pt. contests (rotation players)! (And remember that Boston was fifth in opponent's eFG%).
...and doesn't defensive rebound well (which I consider part of defense).
And you consider that quite properly - the possession isn't complete until the defense gets the ball, and that mainly happens with a rebound. It was all the more important for the 2017 Celtics, since they were only a middling team at causing turnovers.
The Celtics were fifth in defensive eFG% last season, but only twelfth in overall defense. Defensive rebounding, frankly, was a crisis; 27th in drebrate is not just giving opponents a lot more chances at a make - it's also giving them trips to the line. Of the big priorities for next season, I believe that defensive rebounding is THE issue to be addressed, along with shot-creation off the dribble and (not unrelated) depth at the bigs.
So your criticism of Kelly would be [dang]ing indeed - except that, looking at his results, it's hard to justify. His drebrate was 20.7 - tops on the team. (20 is a good benchmark for good defensive rebounding, since 15 is about league average.)
Kudos to him for upping his game in this area, which must have been a point of emphasis (Jae and Avery also responded to the call with real results).
We could add that he was sixth in deflections on the team (meaning, he was in the right place with his hands up, tied into his teammates, focused and mobile).