A conjunction gone rogue

Within the reduced scope, granted, of the subset all sentences I have read which were written by editors employed by a major publication, this may quite possibly be the very worst sentence I have ever read:

Mick is a saxophonist, and the cartoon shows off a barren landscape which is broadly symbolic.

For the information, that Mick is a saxophonist, one is grateful;  the general description of the cartoon's illustration, is arguably a verbal kindness.  It is the conjunction and which invites concerns of potential mental imbalance . . . .