I thought I would take a quick look at favourites in small fields for myself.

Following are stats from the last 4 years for favourites in Sat Metro flat races where the field size was 7 or smaller. I have only included distances ranges where there have been at least 50 races.

Sat Metro - VIC, NSW, QLD, SA

Distance Win % POT %
1000 to 1199 - 42% -6%
1200 to 1399 - 42% -6%
1400 to 1599 - 36% -17%
1600 to 1799 - 25% -44%
1800 to 1999 - 35% -19%
2000 to 2199 - 38% -11%

Take 2YO's within this sample out and races up to 1399m produce a small 1.6% profit at NSW TAB dividends...that could equate to 15-20% profit using Betfair.

Of course these are just stats and its no guarantee such results will ever continue. In any case there has only been 300 instances in the past 4 years, hardly enough to get excited about.