Simple rule of thumb:
If the horse you like is too short on opening then wait until it drifts and clean up. If it stays the same price or moves in further then the TAB have got the price right on opening and there is little you can do about it.
I would like Lazarus to open at 15s in the NZ cup too but it is not going to happen I am thinking.
Agree the place odds open too short nowadays but I imagine they do that just to piss Brodie off.