Thats why when i read the formguide I take note of the early splits as in 13345 which is the dogs progression throughout the race. If the dog has been checked it will have C1-8
eg: 12267 C4
That means that the dog lead early on, was in second and then was probly checked off the heels of the leader rounding the bend. Just because the dog finished seventh doesn't mean its no good. Even if the dog was at 21-1 doesn't mean its a bad dog either.
There is a high percentage of dogs that hit the front by the first corner that win. Watch the races and see that only th dogs who are in form come from behind to win.

Another factor that I make note of when watching the races is the first 5 seconds. This is crucial as you said moeee. You can tell how the dog races during these 5 seconds. If a Box 8 runs straight into a Box 7 it basically means its looking for a rails run. If it's from an inside box and runs out, it means it will be looking for a wide draw as it likes to run around the dogs.
Running wide on turns, or railing home makes a huge difference too. I dont really know what to make of that yet, but it could be to do with inexperience.
Also you can see when a dog bets stuck behind a few runners and just wants to push through, but cant. It then takes the wide run and finishes on strong. But the problem is since it ran wide, it usually finishes where it started from, behind all of those runners. For me, it doesn't mean the dog is too slow, it means it used up too much energy trying to squeeze between dogs and then ran wide, so it would be a chance with a clear draw next race.
Also everyone says winning form is good form. We all know long shots barely back it up, so how can this theory just apply to a select few. Well when any dog wins a race, you must look at the pattern of the race, the incidents and the speed. If the winner came from dead last, it is more than likely to back up. If it won by 8 lengths it is more than likely to back up. If it won due the dogs in front or behind getting into trouble, it may not back-up and if it was a slow race, it wont back-up.

Early speed indicator is what you need to look for along with the general pattern of racing. When i select my dogs I take no notice of what odds it is paying as this may persuade you when you have a 20-1 dog who has finished 88767 in his past five, and you may not bet on it. Just do your tips then look at the odds. As a lot of dogs pay under 3-1 it can be a non-profitable situation. So then if your dog is over 3-1 back it, if not exclude the race. If it wins under 3-1 it will only be a small profit, and there are plenty more bets that come off over 3-1.

Get yourself into a betting routine, dont go bonkers like i did the other week (unless you are filthy rich) and just have some fun while trying to make a few bob.