But I dislike the metric of "record against Top 25 teams" because it is based on stupid polls that use stupid criteria and often lead to stupid results. I don't really care whether a team happened to be ranked if it turns out that team was awful. And, similarly, I don't care whether a team happened to be unranked at the time a certain game took place if it turns out that the team was actually really good.
An example of the silliness of poll rankings as your metric is the recent headline that "Indiana is the first team to lose to three unranked team as #1 in the same season since..." The three unranked teams IU lost to as #1 are Illinois, Butler
Worse, there's really no excuse for relying on polls to be the arbiter of good wins anymore. We've got great rankings, such as Pomeroy's, that give you much better information about how good a team really is, how impressive a victory was, and how humiliating a defeat was. Indiana's loss to Wisconsin is not so shameful after all, if you look at Pomeroy's ranking: based on all the data at our disposal, Wisconsin is a top ten team—and it was a top 15 team based on the available data at the time.
So in examining Wisconsin's road record under Bo, I would rather use Pomeroy's ratings from the end of the season. That way, you know how good the win actually was—not how good it seemed to be at the time.*** The only downside is that the ratings go back only to 2003, so you miss Bo's first year (when he had historic, program-defining road wins at MSU and IU). For that year, I have used Basketball Reference's SRS, which is essentially margin of victory adjusted for strength of schedule. (Better than nothing.) So, here are the results, presented by number of road wins since 2001-02:
***The only argument for using contemporaneous rankings (that is, the rank of a team when it played the game) is that teams do sometimes get significantly better or worse during a season—particularly if they suffer a major injury. But in my opinion that possibility is overstated and, anyhow, those kinds of things should even out in this kind of comparison.