This "viscous shock absorber" thing is the funniest thing I've heard in a long time!!! While it's true that I will use the lightest grease on hand for break cables, the notion that it could measurably slow it down is delightfully bogus.

The old Diacompe aero levers (and I still have a pair on an old Cannondale) are notoriously friction-ey in part because of weak springs and less than ideal routing. I used to dread these on bikes cause it required so much work to get them snappy. Use the best quality lined cable you can and be very picky about the routing of the housing, esp out of the lever. Avoid wrapping over the housing on as much of the bar as you can. Also pay attention to the routing at the rear of the bike.