We are conflating two things here. Whether LMB are "line shy", as are some fish, and does line diameter affect a particular lure's action, and if so, does that affect it's effectiveness negatively.
-LMB are not line shy.
- Yes, some lures will work best with a particular or narrow range of line diameter, and most times, this is what is desirable, but sometimes, particularly when little or no action is desired, going against the grain is the ticket.