You might be onto something there. I've had two pre 78 Mustangs and they never had cracks or holes in their decks but my SuperStart circa 81 has a 6" section of the front skirt pushed in with a crack either side of it instead of bending in from the knock it had.
That's disappointing to hear if it turns out the quality of the aluminium poured into the mould was inferior on a molecular level or due to contamination.

I have a Powerplus self propelled SuperStart with a good chassis. Self propelled system is faulty and motor won't start unfortunately.

Ahh, if only victa had kept producing the thumblatch catcher series, they would be in better shape today!