Flares have to be removed. In most cases its already week and does not support anything.Thats why it is flared.In most cases if proper trimming schedule is keeped flares will be easily controled on horses with no major conformation problems.If flares are not controled it can lead to shifts in the hoof capsule.Shifts can take several trimmings to get back and in some comformations can never really be corrected.I trim 300-600 thoroughbred mares a month.As you know they are known for weak hooves and have rasped many flares off and it always improves the foot quality.as a matter a fact many horseshoers have lost accounts around here for not takeing care of flares. Just my two cents worth.