Not saying you are wrong but think of this....favs win more races early on in the day we have done this before and the winning % of favs starts to decline as the days races are run.....if you take your idea of backing a fav after 4 losses where do you start this...on any given saturday there are like 60-80 races we have all seen days where the favs wins everything and there have been days where the fav could not buy a win i think on these days that you would lose what ever profit you made on other days....not really sure how to back favs maybe some time of all-up system or parlay