Lu Z.
Check with any Dunlop rep and they will tell you how it costs them a fortune to impregnate their tyres with carbon so that MOST of the static charge can be dissipated through the main wheels.
On my a/c type the lead you describe is only fitted to the nosewheel to dissipate any residual.
With regard to the A310 that is interesting but it still does not invalidate my answer to the question.