These are interesting, but I've always felt the best comparisons of roughly equal teams' position within their conferences has always been the bowl records.
Agree for the most part - but for a number of years the B1G bowl alignments/parings have been very bad for a number of reasons.
1. In the last 10 years, there has been probably fewer than 10 bowl games vs non-bcs, Big east or ACC teams. Most of the match ups were vs the SEC (3/4 games), B12 (2/3 games) and the rose bowl vs PAC Champ. Even the SEC has had its share of gimmie bowl games vs Big East, CUSA, WAC teams.
2. In the last 10 years or so, OSU and Mich were selected as at-large BCS teams even though there were higher ranked teams. Mainly b/c they have large national followings and fill the hotel rooms. This had two effects - a the B1G at large was usually going against a higher ranked BCS team. Ex - 2008 when #10 OSU played #3 Texas; Mich/Ill vs USC. The second is that by having an at large bid, it had a trickle down effect on other B1G bowl match ups. That is, you had B1G teams playing higher ranked teams because they moved up in the B1G bowl pecking order. Example, if Mich wasn't selected in 2010 for BCS at large they would be playing against SCar in Cap One bowl and Neb vs UGa, Mich State vs UF.
3. PSU and OSU bowl bans caused some uneven bowl match ups. One year B1G had its number 7 team Iowa going up against B12 #3 Oklahoma (who had been #1 much of the year).
I know this sounds like a mix bag of excuses but the bowl mis-alignments have a lot to do with the B1G's bowl record. Especially when most of the bowl games are vs the SEC which goes 4-5 deep with quality teams, the B1G needs its true #2 going against the SEC's #2 or #3.