What is more accurate: magnetic anti-skating, or barrel weight attached a fishline?

There is an old trick to correctly set anti-skate.Because two (i.e L+R channel) signals out phase with each other will cause a -3db drop in volume when they meet.This is audible.You also need a mono switch on your preamp and your cartridge well aligned. I put my right channel on my cartridge out of phase and put the right speaker back in phase by changing polarity at the input.To find the correct anti-skate position put the preamp into mono.One side is out phase the other in phase.Adjust your anti skate until the signals meet and a volume drop occurs.You have electrically set correct anti-skate.Put preamp back into stereo mode to hear this.

That in practice is not actually the case.I found as most of us have that the last track of a side is the problematic area.Look at Stevenson's alignment method for how far you can take that.Usually a slight increase in anti skate here will deal with this issue.I will grant that it is a get you in the ball park method bottom line.I now adjust by ear anyway.But what it did was to teach me where approximately to set my anti skate so I now can do it relatively quickly.