Renee and Carol, I've been where you are as recently as March. I watched derbies in the past and got a feel for what it took to compete in them and decided to hold off until we were further through transition work. I think a lot of the "scary" suggestions that you're getting are geared toward helping you determine if you can be competitive (if you can place) in a derby, not simply if you can run one.
From my limited experience, if you maintain your training standards, it is tough to get through a water series if your dog hasn't gotten thorough training on de-cheating, angle water entries, angling across points, and down-the-shore type setups (I've seen plenty of dogs that run around corners or beach early and run the bank, but if it was my dog, I would not tolerate that behavior). The bottom line is, you don't know what the judges are going to setup, and so if you want to compete, you have to be ready for a lot of different possibilities.
Prior to running a derby, I asked myself two questions. What is my ultimate goal for my dog? What is my goal for my first derby? My ultimate goal is for a competitive AA dog. My goal for our first derby was to finish it (we didn't). I believe the first answer trumps the second one, so I was determined to maintain our training standards as best as reasonably possible. As I'm not experienced enough to know which trial behaviors I could let slide without causing issues down the road, I was prepared to maintain pretty high standards with regard to handling or picking up.
If your goal for the derby is to simply play, gain some experience, and get as far as you can, then I'll offer this checklist for success in the first series. I made this prior to running one based on my observations of derbies that I’ve worked for our club (in order of importance).
1) Holding blind/Line manners - in training, the dog should walk at heel, off lead, from the holding blind to the line. The dog should sit on line quietly and calmly and watch the birds. For me, the dog should *never* break or creep in training.
2) Picking out guns - the dog should be able to look past the short flyer station and lock on the longer dead bird station. Be prepared for the long bird station to be hard to find, in shadows, and fairly tight behind the flyer station (I've seen a separation as small as about 20 degrees).
3) Returning to old fall area - the dog should be trained to run past the flyer station en route to the longer memory mark. Sometimes, there will be a cover strip (like a hedge row) that the dog will have to break to get out there. I've seen a derby first series where dogs that ran along the hedge row ended up back at the flyer station.
4) Fighting factors - the dog should be able to fight SOME factors, like running through strips of cover and hedge rows, hillsides, and wind (see 3).
In my opinion, if you can do 1 & 2, you will be able to pick up at least ONE bird in a derby. If you can do all 4, you will be able to pick up at least TWO birds (and most likely FOUR, assuming the first and second series are both land).
My final suggestion is to read the rulebook before you run. I think it is especially important to read the “Classification of Faults”. This section can serve as a barometer for where you are in training and if you should run your dog. If your dog commits serious faults or regularly commits moderate faults in training, I would do some deep analysis of my training and my dog, and might think twice about entering a trial.
Finally, a note to Carol: I find your statement that only people who use pros can compete in derbies dismissive of me and many other young amateurs that I know. I have a wife and full-time job, but I work very hard to train my dog (myself) to be competitive in this sport. Sure, we’re out-numbered, but I’ll guarantee you that there are amateurs like me at almost every derby. Please go watch some derbies…we’re out there!
Good luck and have fun!