I think there's an inverse relation between the quality of the arrangement/performance and the time you have to spend "optimizing" the tracks for a mix.
If everything sits right during the actual recorded performance, it will sit right in the final mix.
If there's no performance to speak of as in the case of recording track by track, or recording a bunch of talentless fruitbats, then I agree you have to spend some time "optimizing" to create your mix. Wether this means soloing/tweaking every track or putting up a decent mono mix of the recorded program before going stereo all depends on one's personal production values.
In the end, you have to make it sound good one way or another. Put them faders up and use your ears!
