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It specifically is not. Common opponents are covered elsewhere and, if you click the link, it specifically states that this applies even if the number of games is unequal then gives an examples including that 1-0 is better than 0-0 and that 0-0 is better than 0-1.

that's interesting, in sec it is the opposite. they also have a second provision with common opponents.
first common opp provision is record vs all common non-div opp.
second is record vs best common non-div opp, going down.
also different if the provision for best cumulative record vs non-div opp, which in sec is after those 2 i listed above (last one before coin flip) whereas the b1g is before.

just thought it was interesting.

the program I watched, Bo seemed to think other ADs voted not for Woody and Ohio State, but against him and Michigan because of some hard feelings

He seemed to think it because it was almost certainly true. I recall Burt Smith at MSU nearly admitting as much.

Did this change since 2016?  I remember when it looked like OSU, Mich and PSU might have ended up 8-1, in a 3-way tie, the key tiebreaker at that time was PSU's OOC loss to Pitt.  

Of course Mich ended up losing its last 2 games and finished 7-2,  and PSU ended up 8-1,  winning a 2-way tiebreaker over OSU based on H2H.

I believe so.  It seems to me that they have changed it multiple times.  At one point the tiebreaker was CFP ranking and that created another interesting scenario that failed to materialize:  I don't remember the year, but for a while it looked like the B1G-W would be locked up but the B1G-E would be a three-way tie to-be-determined by the CFP ranking.  Problem was that the CFP rankings didn't come out until (I think), Tuesday.  Consequently, if that had happened the B1G-W Champion would not have known their opponent for three days while all three B1G-E co-champions would have been game-preping for the B1G-W Champ knowing that one of them would get there.  

He seemed to think it because it was almost certainly true. I recall Burt Smith at MSU nearly admitting as much.

Maybe the AD's just voted for the obviously better team:

Opponent	Conf-W	Conf-L	Conf%	L8-W	L8-L	L8-%	tOSU-O	tOSU-D	tOSU margin	M-O	M-D	M margin	Off	by	Def	by	Margin	by
Minnesota	6	2	0.75	6	0	1	56	7	49	34	7	27	O	22	even	0	O	22
Michigan State	4	4	0.5	4	2	0.666667	35	0	35	31	0	31	O	4	even	0	O	4
Illinois	4	4	0.5	4	2	0.666667	30	0	30	21	6	15	O	9	O	6	O	15
Purdue	4	4	0.5	4	3	0.571429				34	9	25
Northwestern	4	4	0.5	4	3	0.571429	60	0	60
Wisconsin	3	5	0.375	3	3	0.5	24	0	24	35	6	29	M	11	O	6	M	5
Indiana	0	8	0	0	6	0	37	7	30	49	13	36	M	12	O	6	M	6
Iowa	0	8	0	0	6	0	55	13	42	31	7	24	O	24	M	6	O	18

If I were the AD for Ohio State or Michigan I would advocate for my school.  If I were one of the other eight AD's I would vote based on which team I thought gave my conference the best chance to win the Rose Bowl and I just can't see how anyone can argue for Michigan on that basis even without the QB injury issue.  
As you know, in our power rankings I look a records against similar teams.  That is what I created the above chart to do for the 1973 season.  the Conf-W, Conf-L, and Conf% columns are pretty self-explanatory.  The L8-W, L8-L, and L8-% columns are Wins, Losses, and winning percentage in conference games not against Ohio State or Michigan.  I did that because in 1973 the "Little Eight" went 0-season against the Buckeyes and Wolverines.  In fact, none of them even got very close.  Illinois got the closest to Michigan, "only" losing by 15.  Wisconsin got the closest to Ohio State, "only" losing by 24.  
Note here that the three places where Michigan did better than Ohio State (Offense against Wisconsin and Indiana, Defense against Iowa) were against the three worst teams in the conference.  Additionally, the teams that Ohio State and Michigan missed (Purdue for Ohio State, Northwestern for Michigan) were reasonably equivalent.  They both went 4-4 in the conference and 4-3 against the Little Eight.  Ohio State's 60-0 win is thus much more impressive than Michigan's 34-9 win.  
Michigan's defense was almost but not quite as good as Ohio State's.  Ohio State's offense was clearly superior.  Anybody who voted for the best team voted for Ohio State.  

hah hah hah
there was no Big Ten Network at that time

I get that, but even before the conference networks I would still have wanted my conference to win the Rose Bowl.  Obviously I'd rather not be an also-ran, but if I have to be an also-ran I'd rather be an also-ran in a top-notch conference than an also-ran in a mediocre conference.  

Considering that during the "TEN YEAR WAR," during which the conference was trash, from 1970-1980 the Big Ten went 1-10 in Rose Bowls (UM 0-5, OSU 1-5), and this was the Big Ten's lone win, a blowout win over USC, I guess it worked out ok,

The little eight were certainly terrible and obviously the 1-10 stretch in Rose Bowls was bad but I do feel the need to point out that almost all of the losses were competitive games.  Those 11 were the 1970-1980 Rose Bowls (1969-1979 seasons).  
There were two big blowouts, USC's blowout of Ohio State in the 1973 RoseBowl (1972 season) and Ohio State's blowout of USC in the 1974 RoseBowl (1973 season).  The other nine PAC wins:

• USC over tOSU by 1 point in 1980 (1979 season)
• USC over tOSU by 1 point in 1975 (1974 season)
• Stanford over Michigan by 1 point in 1972 (1971 season)
• USC over M by a TD in 1979 (1978 season)
• Washington over M by a TD in 1978 (1977 season)
• USC over M by a TD in 1970 (1969 season)
• USC over M by 8 points in 1977 (1976 season)
• Stanford over Ohio State by 10 points in 1971 (1970 season)
• UCLA over Ohio State by 13 points in 1976 (1975 season)*

* I put an asterix next to Ohio State's 13 point loss in the 1976 RoseBowl because I want to point out that Ohio State beat UCLA in the Rose Bowl by 21 points in an OOC game on October 4.  My point being that it isn't like UCLA (and by extension the PAC) was clearly better than Ohio State (and by extension the Big Ten) that year.  They went 1-1 against each other.  

My guess is that it will almost never matter in either conference.  I think that the by far most likely 3-way tie is between teams that split with each other (1-1) and beat everybody else to go 8-1 (B1G) or 7-1 (SEC).  In that case all of those will be tied.  The decisive difference, at least in the B1G, would then be the strength of each team's non-divisional opponents.  

that's true of the sec as well. only difference is order in which the test is applied. in sec, should each teams non-div opp records be equal, it'd go to coin flip, whereas the b1g would still have steps 6-7 available before coin flip/random draw.
would take some stars aligning for those scenarios to pop up.