I think both arguments are valid. A dedicated line will allow your system to draw current independent of the rest of your home. A wire can only carry a limited amount of current before it begins to heat up and limit the draw. This effect can be minimized by running heavy gauge lines directly from your circuit box.
However, this will do little to reduce the effects of noise on the line that a well designed power conditioner will address. I am currently using a balanced transformer with noise reduction (Furman) connected to a dedicated line near my breaker box. I then ran 4 separate lines from the Furman to my gear. The reduction in the noise level was very noticeable. I hope to soon begin experimenting with a PS Audio power plant to see if that will offer any benefits.
However, this will do little to reduce the effects of noise on the line that a well designed power conditioner will address. I am currently using a balanced transformer with noise reduction (Furman) connected to a dedicated line near my breaker box. I then ran 4 separate lines from the Furman to my gear. The reduction in the noise level was very noticeable. I hope to soon begin experimenting with a PS Audio power plant to see if that will offer any benefits.