Yes, I have this same issue, it's seams to be a combination of tramlining and bump steer. The freeways out here are all grooved for rain, I think these tires or the alignment setting do not work for this type of road design.
The guys on the Mustang form use to experience this after lowering their cars, (bump steer) the solution was to put off-set steering rack bushings in to bring the steering rack back up to it's normal position. Seeing that no one on here has a lowered vehicle, that wouldn't be the issue. Wide tires and grooved roads do have some effect on this, but I think the solution may be different alignment specs.
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