garry willis aluminium spacer ball end trick?

[kipsus]

One positive side effect: when used on worn strings, it shifts the worn out spots of the string and prolongs its potential lifetime

 

[stedtale]

I thought the Willis thing was just to pull the string back a little so the windings go over the bridge and not the silk or the tapered windings.

But, couldn't you just used non tapered E and B strings for that? Well...not the silk part I guess.

Willis does say in his book that it helps with the tension, which is a perception at best.

One positive side effect: when used on worn strings, it shifts the worn out spots of the string and prolongs its potential lifetime

Very true, it would move the fretworn spots down/up 1/4 or 1/2 of an inch.