A rerouting from Miami to Ft. Lauderdale is "trivial," but actually expecting you to fly on the flight for which you bought a ticket is certainly worthy of a complaint? I guess your religion would say getting dry crackers is worth a post too, as is the airline actually following its own rules.

Obviously CO didn't cancel the flights to purposefully inconvenience anyone, but -- just as you do sometimes -- the OP "just need[ed] to vent" and was looking for comments. Why give him a hard time?

More substantially, I'm surprised CO didn't make an effort to accomodate the OP in some way - whenever I've had a time or routing change like that, they have gone out of their way to make some minor amends. Maybe try to call the elite line and explain the situation again and see if they go for the Y-up at least one way. That doesn't seem like such an absurd request to me. Good luck!