A line lock wouldn't deter any thief. Very few bikes are stolen and ridden away from where they were parked. Most bike thefts are done with two guys and a van. They pick the bike up off the ground and thrown it in the van and are gone in 20 seconds.
This is exactly what happened to my R6--4:00 in the morning; alarm set, disc lock on, cover on and locked. They picked it up, tossed it into a truck and drove off with the alarm blasting away. My neighbor saw them driving off-less than thirty seconds. It is now double chained with Kryptonite chains and locks, new Scorpio SR-i900 with perimeter sensor and new all black DOWCO cover also locked on. If they really want it, they're going to get it, but hopefully this will deter it somewhat. As a side note, last week the remote for the alarm woke me up at 1:30a-ran out to see a Dodge Ram driving off with their lights off and the back half of my cover pulled up-probably trying to see how the chains were attached. If not for the alarm and chains they may have gotten another. Love the Scorpio alarm, well worth the cost. Damn I hate thieves...