That's incorrect Mark, it would be the same as if the horses finished past the post in A, B, C, D order. If D successfully protested against B then the finishing order would become A, C, D, B. In effect B would be relegated behind D but as C finished in front of D it would retain that ranking - it's no different to the scenario re the dead-heat, one dead-heater can not lose its ranking if the other dead-heater successfully protests - it simply gains the advantage of moving up in the rankings retaining it equal dead-heat ranking by default.