When Teddy Roosevelt went to his first football game, US-style football didn't exist in a standardized form, but was being worked out, from rugby and soccervarious local opinions and customs. Harvard favored something soccerish; Yale liked more rugby style, meaning a player could pick up the ball and run with it.
For this particular game, they decided a touchdown would not create any score, but would create a scoring opportunity.
Now, in US-style football, a touchdown--when a player in the end zone has the ball by carrying it there or catching it there--scores six points and creates a scoring opportunity for one more point, if the team that made the touchdown successfully kicks the ball over the goalpost.
For this game, the one point post-touchdown kick was the only way to score, but you could only do it if you first made a touchdown.
This created low scores, reminiscent of scores now of non-US football, futball, soccer.
It also created ambiguity, as at the end of the1876 Harvard-Yale game. Very close to the end, Yale was ahead 1-0. Harvard made a touchdown and time ran out. Harvard said they should be allowed to go for the point attempt the touchdown allowed them. The ref said no, time was up, that was it. So Yale won 1-0 with no point attempt Harvard, and lots for these young scholars to discuss.
Now, and then, the way to get a touchdown was to have the ball legally in your possession in the correct end zone. Now, one way to do that, beloved and dramatic, is for a player to run into the end zone and catch a throw from the quarterback.
In 1876 and for a good while thereafter, that wasn't a possibility because a forward pass was illegal. The ball could only be thrown across, laterally, or back.
Wimpy liberals helped make the forward pass legal, as did Teddy Roosevelt, long after his student days, as presidents.
Progessives, liberals, those folks, my kind of people, said, as football became more and more prominent, that it was too violent. At this point, college football was what mattered, and broken leges and big gashes on youth were routine.
So some said football should be outlawed. Teddy Roosevelt was president andl iked football and thought the rules should be changed to make it somewhat less violent. He had no direct power over football rules, but one thing a president can do is make a lot of noise and strongly encourage people to talk to each other and come up with a new course of action.
.--facts from "The Big Scrum: How Teddy Roosevelt Saved Football" by John Miller.