Containment seats allow the rest of the safety equipment to do the job they were intended. Roll bars, helmets, seat belts, etc are useless if the driver can move/stretch far enough that these items are no longer offering the protection they were designed for.

This is an argument I've been making for years as opposed to the mandating of head and neck restraints, which have never been proven (or even been tested) to be effective in an upright seated position or in a sprint car. Those devices exist to prevent one injury, and one injury only, a basilar skull fracture, something extremely uncommon in sprint cars (I can find 2 in the past 25 years). Yet the talk is of the magic bubble these things provide because they work in NASCAR or Indycar.

I feel containment seats are the greatest safety advance in the past 30 years. I find it beyond silly to see a driver wearing a head and neck restraint device while buckled into a car with a flimsy seat, no window nets or head containment and their helmet even with the top of the roll cage. They are truly missing the intent of safety at that point.

Kudos to understanding exactly what is causing injury and death and working towards lessening the chances.