The learning curve for the nitro was sure steep and expensive...
Modern tech potentially helps here as it does with the turbcharging learning curve...there are electronic systems out there for both that are hooked up with knock sensors, exhaust temp sensors, etc. that can watch and correct the input very rapidly and so greatly reduce the amount of scrap iron created by the learning curve.
Remember that flatheads last took top eliminator at the nationals in 1956 (I think, from memory) and nitro was one of the factors. That last flathead top eliminator, the Rice car, was built to run with either a flathead or a hemi and was run in both configurations...the flathead was chosen over the available Chrysler for the nationals.