Anti-lag is common on turbocharged/EFI cars in many forms of racing. It's a combination of wastegate control, retarded timing and very late injection that will keep the turbo spooled up. You're essentially moving combustion to the exhaust manifold and turbine housing. Without fueling, if the turbos have variable geometry you can accomplish almost the same thing, but I'm not sure VGT's have appeared on gasoline powered race cars yet (almost all diesels now are VGT).

Durability isn't a problem but I wouldn't expect the IMSA guys to be using it as aggressively as something like a WRC rally car. IMSA is much more dependent on fuel strategy as a whole.