Do you run into a lot of trail and error with shooting action shots like that? You know, dog running at you at f/2.8. Probably 90% of my shots come out out-of-focus. It's so touchy!
Yes 100%, there was a HUGE change when I went to a 7D from the 50D, it went from that 90% to about 75 or below, depending on what I'm shooting. For agility trials I used to barely have 200 good shots after shooting 6K worth of photos, but now I tend to have about 1K keepers.
That makes sense about upgrading your body. I have a entry-level DSLR and I bet when I move up it'll help a lot!