During a year the bowl is used as a playoff bowl, the rules state it will be #1 vs #4 and #2 vs #3. The bowl closest to the #1 team will host the #1 vs #4 game and the other will host the #2 vs #3 game.
The bowls are rotated in pairs - Rose/Sugar, Fiesta/Peach, Cotton/Orange. I find it coincidental (or not) the bowls are "geographically spaced out" the way the are. From West to East (ish) the bowls are Rose/Fiesta/Cotton/Sugar/Peach/Orange which puts them together as 1/4, 2/5, 3/6 if that makes sense.
The tie-in responsibilities:
Rose Bowl - playoff matchup OR B1G #1 vs PAC #1
Sugar Bowl - playoff matchup OR SEC #1 vs XII #1
Orange Bowl - playoff matchup OR ACC #1 vs SEC #2/B1G #2/Notre Dame
Fiesta Bowl - playoff matchup OR AT-LARGE vs AT-LARGE
Cotton Bowl - playoff matchup OR AT-LARGE vs AT-LARGE
Peach Bowl - playoff matchup OR AT-LARGE vs AT-LARGE
Orange Bowl Special Rules
1) During Rose/Sugar playoff years, if the B1G and/or SEC champion is available for a non-playoff bowl, that school can't play in the Orange Bowl
2) During the Orange's 8 non-playoff years for the current playoff contract, the B1G and SEC are guaranteed at least 3 appearances and Notre Dame may not appear more than twice
3) During the Orange's non-playoff years, if the ACC #1 is available for the Orange and the matchup vs B1G/SEC/Notre Dame creates a rematch, that team may be passed over but will be placed elsewhere
4) During the Orange's playoff years, if the ACC #1 is not a playoff team, it will be selected for the Peach or Fiesta
Other Special Rules
1) The highest ranked Group of 5 team will play in a major bowl if not in the playoffs
2) For the non-playoff major bowls, the committee will select the "most compelling matchups" while taking into consideration geography and rematches from recent seasons/bowls
1) Who in the world made the Orange Bowl so special and why?
2) In a year BYU, Army, or another non-power independent (Navy this year because they're independent) is higher ranked than the highest ranked Group of 5 team AND they get selected for a major bowl (e.g. BYU finishes ranked top 10 this year and gets selected for the Fiesta Bowl), does the committee have to select the highest Group of 5 team or does the independent school count as the mandatory Group of 5 representative?
3) I know bowl games matchups are created by contract, but why do the SEC #2 and B1G #2 get special treatment for the Orange when it may be likely at some point they would not be qualified to play in it (e.g. look at how poor the B1G looks so far this season)?
4) Would it be a bad idea to tie-in Group of 5 conference with major bowls (in case that bowl is available for a non-playoff game and the Power 5 tie-ins aren't available) in the case that one of their teams gets a bid to a major bowl (e.g. MWC with Fiesta, MAC with Orange, SBC with Sugar, CUSA with Cotton, AAC with Peach, Independents with Rose)?
5) I've been a strong proponent for an 8-team playoff with the Power 5 conference champions getting auto-bids. However, after some consideration, I think this would be a poor decision. Take the SEC for example - 8 conference games & 4 non-conference games. It is likely (not probable) the champion could go 4-8 which would be a terrible team to give an auto-bid into the playoffs.
Other Ideas/Questions/Thoughts are welcome for discussion!