The real problem with this seems to me to be that, as Chuck says, it fits the data by construction.
Incidentally, when Einstein was developing GR, there was a theory around the time about modified gravity too. The only real problem with Newtonian gravity at the time was that it incorrectly predicted the precession of the perihelion of Mercury. So the modification made was that instead of gravity going as the inverse square of the distance, it went as the inverse of the distance to the power of 2.000002 (maybe not the correct number of zeroes there, but you get the idea). This fitted the data quite well, but it's a horrible ad hoc "solution".
This idea to explain rotation curves seems like a similar kind of ad hoc solution to me.
Incidentally, when Einstein was developing GR, there was a theory around the time about modified gravity too. The only real problem with Newtonian gravity at the time was that it incorrectly predicted the precession of the perihelion of Mercury. So the modification made was that instead of gravity going as the inverse square of the distance, it went as the inverse of the distance to the power of 2.000002 (maybe not the correct number of zeroes there, but you get the idea). This fitted the data quite well, but it's a horrible ad hoc "solution".
This idea to explain rotation curves seems like a similar kind of ad hoc solution to me.
Galileo was a man of science oppressed by the irrational and superstitious. Today, he is used by the irrational and superstitious who claim they are being oppressed by science - Mark Crislip
