With digital, you can also use fighter missile doctrine of "Shoot, look, shoot". When Navy was dumping film on me, I used your technique to "bracket" my shots with different settings, but I wasn't paying for film or processing unless I was ashore shooting personal subjects. You learn quicker and like you say, some will turn out. He gets (or got ) very expensive shooting that way out of your own pocket. When digital matured, I paid less for my Canon EOS than I spent on film and processing the prior year and I don't have to go hunting negs or slides all the time when someone wants a copy.
Back to "Shoot, look, shoot", I was had gotten pretty good at shooting wet film by mid nineties with 12 magazine covers (including Proceedings, Armed Forces Journal, Seapower and AvWeek, which are all very discerning) and interior shots in all major aviation magazines. So I felt I was in peak form when I decided to go digital. The simple feature that allows you to review what you just shot is amazingly useful in teaching you what works. Even when i bracketd my shots in wet film, the turn around time was so long that it wasn't an immediate learning point. I felt my shooting went to another level and rarely, if ever, have to use photoshop or any editing tool to enhance my images. I noticed that my percentage of good shots versus throwaways increased substantially and there was no cost relative shooting more (although I invested in six flashcards and six batteries and two chargers, but even that was no where near what I was spending in wet film purchases and processing). I also like not having to cart around ten rolls of film and risk missing a shot when changing film (even though I could do it without even looking). Also handy not to have to carry 2-3 cameras (in my hey day of aerial shooting, I always had a camera loaded with C-41 (print), E-6 (slide) and sometimes Kodachrome (ship didn't have it nor could process it so that was on my dime).
Just my 2 cents.
