Spin418......Having experienced the whole spectrum with Becky (this is Dave answering btw) I have to say that passive watching/photographing/videoing is my preference. However. there is something to be said for waiting at home when she says she's 'working late or whatever' and not knowing exactly what she is doing.
I hear what you're saying, but not having experienced it, I do feel like I'd want to be there....for everything. Not to control it, but to share in it. I wouldn't want to be too pre-occupied with documenting either, though I'd love to have at least something capturing a bit of it. I'd want to be fully in the moment with with her and him. I can't imagine anything else, but I'm understanding of the idea that things can change.........and evolve. Heck I'd never have imagined being turned on by something like this in my 20s 30s even 40s.