Not sure if this follows but in 1959 Lehigh's Ed Hamer (4th seed) beat Duane Murty Ok State (champ 1958 and top seed) and Tom Alberts Pitt (champ 1957 and 3rd seed)
They gave the allowance that season- maybe in January(?), but I believe they gave it as an allowance rather than as a new weight. The next year they changed the weight classes in the rule book.
That's up to the school statisticians. Admittedly, I don't know if any school is doing that but career record is not an NCAA issue.
Those bouts do count towards the opponents.
Not sure I can easily explain but you can increase the possible number of cons matches when the pigtails are symmetric top to bottom. On my phone, don't feel like looking it up but this might be what happened here.
When they change the speed limit do people sue because they used to be able to go faster?
When they made the Heil rule going into his senior year, did he sue because he used to be able to look at the lights without penalty?
Originally it was rare to see many 6th years given because the intent was that they had 2 season ending injury years.
It became more common as the rule was loosened and allowed one serious injury year if that came after an earlier red shirt year (I think as a first year but not sure).
I don't think the theory behind this idea was to give them an equal chance to what was before because it was getting out of hand.