Crosstalk (in the context of laserdisc) is indeed a type of interference - which is why the artefacts look similar.
In this case it's nothing to do with RF (so cable shielding won't help) but a disc mastering defect which results in the laser pickup reading a signal from an adjacent pit track that interferes with the signal from the main track.
It was discussed here:
http://originaltrilogy.com/forum/topic.cfm/Smear-free-93/topic/12190/page/4/