Comment 2 for bug 895037

What happens to the MC link when the parasite is evicted from the host?

Proposing

[Unit]
DrawMCLinks = (always|selected|victim|never)

"always" would logically refer to drawing the links all the time, so every player would see them, which will most likely cause lag.
"selected" (default, like right now) is a special case as is: when the source of MC is selected, links are drawn to all of its victims, when a victim is selected, only the link from it to the source is. That can be changed if necessary, although I can't see that being needed.
"never" is just that - never drawing the link at all. This is kinda unfair to the victim player, not knowing who is controlling their unit. Therefore
"victim" is also an option, meaning when the victim(s) of this unit get selected, links from them still get drawn, but selecting the source unit doesn't draw any links.