Does anyone have any rules of thumb about water spots, besides just "get them off the car as quickly as possible?"

I have a new Metallic Black BMW. It had a Sealant with a Carnuba topper on it. It rained earlier in the week, and there were a couple water spots left over. I didn`t think much of it, given that I had 5+ coats of protection on it, I figured I could take my time.....wrong. I ended up having to polish the suckers out using a D/A. I am now paranoid about water spots......

1) Are certain LSP`s better protection against water spots?

2) How many days does it take a water spot to eat through a LSP?

3) Any tips for "diffusing" water spots? I`m trying to figure out if the car is dirty, too dirty for a quick waterless wash, do I go ahead and take that swirl risk to avoid the water spots? Or could I possibly just soak the spots with some sort of waterless/rinseless mixture to dilute them without touching the car, until I could give it a proper wash?

My concern is that I may have to wash this thing daily in the summer, it rains every dang day!