jaffa,

Have to disagree. I have bet dogs in UK and OZ for over 25 years. You have to treat each race and each dog on its merits relative to the other dogs in the race.
I have taken 6/4 plenty of dogs that were entitled to be 4/6.
An example only last Friday where I backed a dog in the last at Casino at average tote odds of $7.00 plus. It had Box 4. Its name: Who's an Express.
Best sectional time for first 50 metres in the race. Slow beginners drawn in 2 and 3. Dog 1 a railer who doesn't leave the fence. Box 5 an average beginner who runs straight for the first few strides and then wants to get off the track. This took care of the outside brigade.
After considering the above, you would have to agree that Who's an Express was boxed beautifully in the 4. On top of that, the track was greasy from the light rain and Casino is a tight grass track that suits leaders.
I had $200 on all three totes for a very nice collect. It led all the way untroubled to win like an odds on chance.
So you see, you have to treat each race on its merits and each dog's chances should be assessed relative to the other dog's habits and racing style.

I only bet on the tote nowadays as I was barred from a couple of well known online establishments. Started with a miserly $5K at a certain book and in six months had increased the bank to $57K betting around $400 per dog and having about 30 bets per week. All of a sudden my dogs started shortening up late on ALL totes. I got sick of it and rang management - their reply was that they really only want recreational punters - in other words, you are not allowed to win. I closed the account immediately and have happily bet on the tote ever since.