Nobody finds it coincidental that the ratings boost Letterman had in October is during the same time frame as his tabloid scandal, and that Conan's ratings hit absolute rock bottom when Leno became his lead-in back in August?
Sure, it's not coincidental. But really, is a Leno viewer interchangeable with a Conan viewer? If the response by Team Coco is an indication, that's a vehement no. Leno at 10:00pm most definitely chased away
NBC viewers, myself included. But, why didn't they return for the local 11:00pm news? Maybe they did and then turned off Conan. Arguably, most viewers have a closer "relationship" and stronger affiliation to their chosen local news team than late night hosts. If they tuned out because of Leno, why didn't they flip the dial back to Conan at 11:35pm? I mean, what viewer was lost? If Leno did anything, those people with Nielsen-equipped TVs who fell asleep while tuned to NBC were awake enough at 10:00pm to hit Power on the remote to escape his "comedic stylings." So, basically, Conan lost the Zombie audience. Not good.
The simplest explanation seems to be that the audience just wasn't there, Leno or no Leno at 10.