Value in Rank Outsiders during low volume mid week races

[ajwisely]

It's midweek, and the volume of traffic is too low to explore any real profit trading on favourites however I was watching the outsiders market fluxuate with interest.

There seems to be reasonable potential to trade as large amounts of money are placed on favoruites and the outsiders drift from 30/1 out to 100/1+ even at small volumes like $4.

People appear to be offsetting by 1 tick, and blowing out the odds i.e. laying 45/1, backing 50/1 for $4 making $20 profit and repeat at 55/1, 60/1 etc

The obvious risk being liable for -$2000+ if you cannot rebuy higher.

Has anyone explored this with success / failure?

The other question to ask is at what point does it become a mistake to not invest $4 when someone has blown the odds out ridiculously, irrespective of the horses ability... 50/1, 100/1, 190/1, I even saw 300/1 offered yesterday (and the horse came 2nd)