G'day GeneralGym,

Yes, conversely, the smaller the field should mean that a competent jockey should be able to steer clear of any interference, so theoretically, this should be to his/her advantage.
Alternatively, could it be argued that because it is a small field, the rider can't get any cover so has to either make the pace or ride his mount "upside down," meaning he/she is unable to let their mount settle properly therefore expending more energy to get into a competitive position early, leaving it with no reserves for it's finishing run.
I'll be watching this closely to see if there is any leverage which may help us turn a profit.

Cheers.