So metrics aren't a good foundation but you've used them to try and prove Chris Paul isn't an elite defender?
The stats I used in the OP and throughout this season give a more accurate reading - not perfect - but certainly more accurate. You can't use defensive metrics as foundation like DRTG/DWS when measuring a player's defensive impact, especially ones who aren't anchors.
Can you actually mathematically explain why these aren't good? Since I have a background in stats and sports betting I'm sure you'll set me straight.
- The plague of multicollinearity
- The variance and ability in team defensive anchors and scheme throughout the league (not one situation is the same for any guard playing starters minutes)
- The defensive workload and defensive distance traveled/speed per defensive possession (dependent on scheme and personnel, especially for PGs)
- Inability to determine who has the most defensive impact on any play due to all players on court being equally rewarded (not all metrics, but most)
- Too box score dependent, while undervaluing other area
- Strict formulas not allowing for basketball play variables and outliers
But Chris Paul actually rates higher than Mbah, and even before he was on the team CP3s ratings were high
Rates higher on what metric? And you really going to sit there and suggest that CP has had more defensive impact this season?
But this doesn't mean he's a bad defender, it means he can't contest shots well which is obvious when he's 6'0.
Yes it does actually, because it doesn't measure your effectiveness of contesting shots but just your activity of actually contesting the shot. Not is/was he bad at contesting shots (size has nothing to do with it as you can still actively contests shots if you're of short statue - being short doesn't take away your ability to contest shots, especially if you are guarding players that are of similar height - which CP is typically doing), but he was also bad at keeping in front of his man too -
77th among PGs in Keep-in-Front% at 29.7 - "Keep-In-Front% tracks a defender’s ability to keep his man in front of him following on-ball screens, during help attempts, on one-on-one drive attempts, and on closeout attempts."
However, a closer look at Paul’s numbers show that it’s not just on-ball screens where the point guard is having trouble keeping his man between him and the basket. His Keep-in-Front Drive% was just 35.9 percent on the season. In comparison, the Boston Celtics’ stalwart young defensive unit of Marcus Smart and Avery Bradley had Keep-in-Front%’s of 53.8 and 50.8, respectively.
Not matter which way you try to spin it, that isn't the mark of an great defensive guard.
What about all his PnR defense,
See above re: on-ball screens. He was poor in that department (more inconsistent than anything else - picking and choosing when to play defense).
elite steals without gambling and breaking the defense,
That's exactly how CP has managed to keep up this facade for so long - gambling. Because he sure as hell isn't great at many other aspects of defense.
picking up transition, bumping cutters - all stuff you don't need stats to see?
Funny how metrics are useful to you now 
Those aren't metrics, not in the APBR sense - they single out an individual's defensive impact during a particular play: Keep-in-front%, contest rate, defending ISO/ball-handler/off-screen/spot-up attempts. While they certainly aren't perfect (no defensive stat is), they give you a more accurate reading.
You going to show the videos where CP3 murdered Lillard this year too?
Before we get into that, care to explain why such a "great" defender looked so bad during that series? I bet you were of the belief that Lillard's low FG% was down to Paul's defense during that series weren't you?
