My 2 at each position.
PG-Wall, Smart
SG-AB, Butler
SF-Kawhi, LeBron
PF-Green, Davis
C-Jordan, Drummond
Forgot to add things I feel carry weight. Rebs, on ball defense, steals/deflections, drawing fouls O&D, quickness, play recognition/help D, and instinct are important to me. An occasional block is always great too.
Using your qualifications, can you demonstrate how Marcus Smart and Avery Bradley are top 2 for their positions?
I'm seeing a lot of people listing their qualifications ("on ball defense" for instance), but they aren't showing how the player compares with the rest of the league. Can you conclusively show how Avery Bradley is best on ball defender in the league? Isn't there a stat for it? Does he rank 1st in that stat?
What I'm still seeing is just opinion-based. Most of this is "eye test". "I think this guy is the best, because I watch him and he looks like the best". It's strange how massive the disparity is between our understanding of offensive excellence and defensive excellence. I can sit here and tell you Steph Curry was the best offensive player in the league, because I look at things like scoring efficiency and total points... but then I can conclusively back that up by showing you how he ranks in things like TS%, eFG%, etc.
Nowhere in this entire two page thread has anyone backed up their list with actual evidence. Pho listed some qualifications that seemingly we could actually look up and analyze. But I don't see a single stat in this thread so far. That's really interesting to me. The closest thing I've seen to a "stat" is someone listing off Rondo's Defensive awards. So he was the best, because someone else said he's the best... and the stat to back that up is that someone said he was the best.
To be clear, I'm not trying to discredit anyone's list. These might be totally on-point. I'd just like to expand our defensive knowledge beyond word-of-mouth, the arbitrary "eye test", and general perception.
If Smart and Bradley are genuinely the two best at their positions, there most be some evidence to support that. That's a pretty big deal if true. Can anyone prove it?
I'm not a stats person, but here is my two cents.
Offence is easier to quantify than defence: in D you have too many intangibles + too much depends on who you play against. For instance, Iguodala got a lot of credit for stopping LBJ in but his performance is impossible to pin down
exclusively through statistical analysis- one literally needs to watch the series to appreciate his performance.
DRPM, DWS, STL%, TRB% etc are all good, but you still need the eye test to assess defensive performance. I would also add to this a good understanding of a team's defensive plan: stat padding can happen in D too.
ofc this leaves the window open for fanbases to be biased and for the media to rely on stereotypes. but I would make the case that this shows why we need
more informed expert opinion for defensive performance; metrics are great for comparisons and to test one's opinion against hard facts, but they will never substitute the eye-test.