A reverse is two IF bets.
If team A wins, then play on team B
If team B wins, then play on team A
If you lose both it is same as playing 2 straight bets. If you win both, you get paid twice on each. If you split, you win one and lose two, yielding a 1 unit loss.
I personally prefer these over 2 team parlays. You take on some extra risk, but the extra payoff is usually worth it (v. the parlay payoff). A split (which seems to at least be my most common outcome
) is basically the same as splitting (losing) the parlay.
Sorry if I stepped on your toes infinii by answering.