IjuandaQLD, yeah it's frustrating isn't it? A similar example occurred in Sydney on Saturday but luckily the horse still won. The apprentice on board was chasisted by a leading trainer about "dropping his hands" on the line.
Don't some of these riders realise the volume of money wagered on some of their mounts and the importance of the finishing order to exotic bettors?
It's a worry as all we punters ask is that the horse upon which we have wagered is given every chance and that includes riding the mount out to the line even if it can't win.
Oaksnaf- it seems that you have no trouble finding winners at the trots but as you said it is difficult to win in the longterm backing shortpriced runners.
Could I suggest you give consideration to having an all-up bet on your three runners, either for the win or the place. Each new bet starts a new sequence, eg. if you had 5 winning bets in a row and you were having a three-leg all up you would achieve 3 successful sequences and should return a respectable POT, eg 123, 234,345...you could take your original stake out and only all-up your winnings so the worst you can do is to at least break even. At least this gives you a bit of insurance when wagering in this manner.

Cheers.