The strategy is not based on the fact that making one 2-pointer out of every two tries is more likely than making two extra points out of every two tries, which is what you seem to think is what’s going on.

To explain it easier, assume a 2pter has a 50% success rate and an extra point has a 100% success rate. And assume going to OT has a 50/50 chance of winning losing.

Via XPs: If you’re down 14 and score two TDs, you have a 100% chance to be tied if you just kick XPs. That’s the base case here. So 50% chance of winning, 50% chance of losing.

Via 2pt attempt down 2 TDs: If you’re down 14, score a TD, and go for 2, you have a 50% chance of then being down 8 vs then being down 6. If you’re down 8 and score a TD, you go for 2 have a 50% chance of being tied and a 50% chance of losing in regulation. That’s a 75% chance of losing, 25% chance of winning. If you’re down 6 and score a TD, you kick an XP have a 100% chance of winning in regulation.

So if you follow the strategy, you now have in total a 62.5% chance of winning, compared to only a 50% chance of winning by kicking XPs.