Good idea, so long as it is not overused,
My only concern would be master scoresheets getting messed up if they are going to change slips to knockdowns and knockdowns to slips. How will that effect the judging and the confidence of the officials involved? But at least it attempts to correct a wrong. Now my understanding is that the corner chief second would be able to request a review of a round during which the call in question is made. The commission could let the original decision stand, overturn it after review at the fight, or wait till a later time. (At least that was the rule in New Jersey.)
Start slow and see what happens with anything new. I also like the idea of only 1 challenge per corner per fight, so that the system is not abused. Make your "challenge" count and mean something for an overtly wrong call. But it's only as good as the people applying it. Let's see Chavez Jr. get a decision overturned on a questionable ruling in Mexico! How well can fairness and neutrality come about through experimenting with the new rule? In order to be in affect in the USA, it would have to be approved by a majority vote of the Association of Boxing Commissions. We have to wait and see what happens in Mexico before we even THINK about a more global change.
At least this is 100 times better than that Open Scoring shit that the WBC tried to bring back. It BOMBED in the USA and justifiably so.