When I started I was lucky if I finished with the group. Attack attack attack is all well and good if you have the capacity for it, but I suspect many first time racers don't. Even now, some races I'm happy if I can even get near the front, let alone attack.
This is true but as a cat 5 if all you've done for 10 races is sit in what do you expect to have happen in a Cat 4 race? At some point you've got to try or all you'll ever be is pack fodder.