I keep my damper very tight. As in, about a 1/4-1/2 of a turn from from being completely bottomed out tight. The only time it ever caused an issue was the very first time I went around the block, I didn't know what the damper was, so just tightened it. I almost dropped the bike 3 times before I realized what I did.
On my machines that had friction steering dampers I was comfortable with just a wee bit of tension for average riding, & slightly more for Highway. To much friction would cause the rolling Steve Thackery mentioned. Sidecar use requires even more tension. My Russian rigs would shake their head at 19mph, This would go away at 21mph. It was un-noticeable if you were accelerating quickly past this speed.
Friction damping goes far back in motoring history. Motorcycle girder forks & springer forks would rely solely on friction rebound damping before Hydraulically damped shocks were made. Antique autos with leaf springs were fitted with knee action Friction Dampers on all corners, that served as shock absorbers. I owned a 1949 MG that had them.
Friction Dampers on motorcycles work pretty much like the Hydraulics, but are much simpler & more compact. They are intended only to produce as much drag on the steering (as determined by the rider) to overcome various road conditions & aid the rider in controlling his machine. I think hydraulic dampers are unwieldy & wouldn't use one if it were a gift.