This very topic cropped up about 12 months ago I'm sure but I recall 2 points out of it:
1. Flying offset is all well and good as long as everybody flies right of track!
2. ATC had a bit of input on the other thread indicating that flying offset (but not advising ATC) causes minor headaches when they try to estimate separation at converging intersections as the times they calculate might not reflect reality since the actual intersecting point is different.