Interesting result Townsville race2 ..Just shows the price variability on Betfair..The lay selection Fraction was 3.2 favorite on Betchoice . driftingto 3.6 SP 3.5 ..Unitab 5.00 fixed . Tote Paying 6.7 .On Betfair drifted from 5.4 ..( I layed it at 5.5).. Remarkably it drifted to 14.00 with BFSP 13.4 . I hedge a small amount at 13.00. to cover my bet.. The point i am making is any system requires a great degree of common sense.Like any position betting or laying if a position becomes available to lay or back a price way over or under the reasonable value then you have to take it.