Teams are quietly buying back the offensive rebound

The decision to send nobody to the glass was a trade made for transition defence, and the price has risen.

Five players retreating the instant a shot goes up used to look like discipline. Increasingly it looks like a team giving away a possession to prevent a smaller number of possessions that might not have happened anyway.

The original logic was sound. Crashing the offensive glass leaves you outnumbered going the other way, and a live rebound to a running opponent is the most efficient sequence in the sport. If the extra offensive board arrives once in five attempts, and the cost is a fast break every second time you send bodies, retreating wins the arithmetic. So everyone retreated, and it became orthodoxy, and orthodoxy stopped being examined.

Two things then changed. Defences got better at retreating in general, which lowered the value of the transition attempts you were preventing. And the miss profile of a league shooting far more threes changed the geometry of the rebound itself. Long shots produce long misses. They come off further from the basket, at flatter angles, and they are less reliably collected by the tallest man standing under the rim, which means the contest is happening in a region where a guard sneaking in has a genuine chance.

That is the crack the smarter teams are exploiting. Not five to the glass. One, sometimes two, and specifically the man in the corner or the wing on the weak side, whose recovery distance is short and whose position on a long carom is good.

I would go further than most and argue the retreat has become a habit rather than a calculation, and habits are where edges live. If your opponent shoots a lot of threes and does not push hard off a defensive board, sending two is close to free.

The interesting counterexample is a team with an elite rim runner. Against them, retreat everybody, always, and accept the lost boards without complaint.

Which is the real point. This was never supposed to be a philosophy. It was supposed to be a matchup decision, and somewhere along the way the sport turned an answer into a rule.