Tramlining, as the name implies is a tendancy for the wheels of a car to follow the longitudinal ruts in the road as found in highly worn lanes or where heavy truck traffic is common, funnily just like a tram following its tracks. Its exacerbated by wider tyres as they hit more irregularities and varied offsets which affect suspension angles. Worn components only allow tramlining to be more pronounced rather than causing it. performance wheel angles such as camber and caster make it harder to manage once the car begins to follow the ruts.
Cheers,

Justin p