I'll chime in with my two cents:
When I began writing a few years ago, I had designs on selling scores to ensembles for performance (lol, talk about naive!) Coming from a performance background, I was one of those that wrote very little down when learning music. Many colleagues mark up their performance scores so much that you can barely make out the actual notation any more. I find this especially true of string players (often out of necessity, not simply because they're OCD!) I was able to commit my musical choices to memory quickly, and also enjoyed the interpretive aspects of performance, which were actually easier to make without being influenced by a myriad of articulation/tempo/dynamic markings, etc. But I digress... Recognizing the requirements of other musicians, my wife, Becky, and I did our best to dot our I's and cross our T's. The first round of orchestral scores and chamber pieces were meticulous in their detail. I told myself the extra time spent would be worth it. It wasn't. At least not when your "colleagues" expect you to put dozens of hours in to scores only to have you hand them the score for free and be grateful for a mediocre public performance at best.
Since then, I found I'm writing faster than Becky can keep up with the copyist services (for which I pay her generously with food). I also found that upon importing perfectly done up scores from Finale to Cubase, I'd still spend just as much time refining things for a midi rendition of the work, whether I imported a score complete with dynamics, articulation markings, etc. as one that was simply "the notes." Actually, I found myself more liberated to interpret the music in Cubase by playing in passages in a way that might have been restricted had I been following my written instructions precisely. In other words, I'm now doing what I've always done as a performer: creating an interpretation in real-time; revising things as I go, also with respect to making decisions based on the idiosyncrasies of the virtual instruments.
Now, many of my more recent scores sit in a state of "partial completion." I will complete the midi-mockup to the best of my ability, but won't go back and polish up the score, until such time as a demand for it emerges (as in, never...oh the cynic I've become!)
In my estimation, the recording of the work reflects the composer's musical sensibilities/interpretation, as it is necessary to make all those choices during the process of creating the mockup. It's not that we "can't" put those instructions in the score, it's that we choose not to for reasons like you alluded to above.
That said, Mike's arguments are equally compelling and if time were no object...
Dave