This is an article today from The Tampa Bay Times, written by Thomas Bassinger. It goes over the forward pass rule behind the line of scrimmage. As well as the 3 point conversion and elimination of extra points.
The intriguing part in the article is Oliver Luck addressing the kneel down.
The Comeback Period”
In the NFL, the game clock stops with two minutes left in the second quarter, two minutes left in the fourth quarter, after an incomplete pass, when a player runs out of bounds or when a team calls a timeout. In the XFL, the clock will stop after every play during the final two minutes of each half.
“We didn’t want a team to be able to have three downs where they just kneel it and burn off 1:40,” Luck said. “A kneel-down — as a quarterback I loved it (he played for the Houston Oilers from 1982 to 1986) — but it’s also a nothing play.”
He calls the final two minutes “The Comeback Period” because we should see a bunch more drives than we’re used to. The goal, of course, is to not only increase the number of games that are decided in the final minutes but also hold the audience’s attention longer, no matter the actual probability of a comeback. After all, late-game comebacks are more rare than we think. Over the past 10 seasons in the NFL, teams that had a lead after three quarters went on to win more than 80 percent of the time.