Moving and blending the 76 hood scoops, you effectively end up with a 69 TA hood!
Apart from its obvious rarity and value today, I'm not terribly a fan of the original TA looks.
Formula hood scoop evolution by
Aus78Formula, on Flickr
The 77-81 hoods have a few notches in the bracing to assist in being the area where it kinks during a smash. I'm not sure if that's the case with other years as never owned one or looked that closely. So it may not be a case of better reinforcing, but changed design for a purpose. They often have cracks just forward of the hinge mounts too where there is a large cutout for drainage, or to assist collision perhaps, but it is obviously a flex weakness made worse with bad hinges. I've owned 3x 77-81 hoods and 2 had it. Again, not sure if this is a feature of other years. A TA hood with a giant hole in the centre would likely flex more than the same version in non-TA, not because of the sheetmetal but the full bracing which remains.