I had a similar idea.
Going by the RAW, Erick and I are, AFAIK, right, and spells like that are perfectly legit.
Sadly, this was flamed down by Rival Magic, IMO exactly because of Moon Duration waiting spells. Serf's parma, but the last page of the ward guys makes that an impossibility. I don't remember very well, but, while speaking of integration, it states something along the lines of "hermetic magic can't do non-ritual waiting spells", and goes on to say that, with integration, non-ritual versions of watching wards would be possible (thus implying they aren't).
I'm sorry for my bad memory, so I advise you to check it, but, as far as I can remember (and understood), we're toast 