This is why Halo Reach will outsell Halo 3! Just do the math people!

[Reasonable]

All I'm going to say is I think the logic behind your deduction is a little suspect.

Reach might very well sell more than Halo 3, if it's good, get's everyone who bought Halo 3 on board plus brings in some new players.

I doubt campaign length or strange comparisons of ODST to Halo 3 are the way to judge this.