Cactus Music
I think the problem comes from trying to do two steps at the same time.
Mixdown = Balancing of the mix and export to a stereo file.
Mastering = Top and Tail and polishing of the stereo file.
So for me it's not an issue because I top and tail during mastering.
I do this in a Wave editor but pretty simple to top and tail a stereo track in Sonar with slip edit.
I think this is a really interesting point
IMHO the advent of "in the box" mixing and more powerful computers/laptops means that the line between mixing and mastering is becoming very blurred from the traditional approach - where it is now possible to do both simultaneously (I didn't say "better" or "desirable" - just "possible")
Back to the start/end discussion
Just because I have found a method that has become second nature and I don't even give it a thought doesn't mean I wouldn't welcome a specific START and END marker that is the default "select all" timeline region - I would find this OPTION really helpful but would still want the option of selecting regions for the purposes of cue writing