When you're an option team, going for it on fourth down is almost a foregone conclusion. Army, Navy, and Air Force all ranked in the top three nationally this past season in fourth down conversion attempts and I'd venture to guess that the vast majority of those were short yardage situations because they took care of business on first, second, and third downs.
While FAU attempted the most fourth downs this season, It was Army that really did something special. In 12 games, they went for it on fourth down 36 times - which works out to about three times per game - and they converted on 31 of those attempts. That works out to an incredible 86% conversion rate.
A Reddit/CFB user named u/Shamrock points out that might be a major college football record. To prove his point, he compiled a list as far back as he could find the data for, which happened to be 2004.
Below is the chart, via Reddit.
While many teams have gone for it on fourth down more over the years, no one has done it with the precision execution that Jeff Monken's squad did this past season. The next closest team conversion percentage-wise is the 2011 Air Force team that converted at an 81% clip. While the research only goes back to 2004, I'd bet that the 2018 Army team is one of the, if not thee, most dominant 4th down team in college football history.
For what it's worth, Army was the best team in the country at converting 3rd downs as well, going 105-for-189, which works out to converting a first down about 56% of the time.
Many of us hope that one day a team will adopt the Kevin Kelley philosophy at Pulaski Academy where they play the numbers and go for it on every fourth down (no matter what), onside kick every time, and go for two every time instead of kicking extra points. But until then, we'll have to appreciate what Jeff Monken and Army are doing on fourth down, because that's the closest thing we have.