It would be an amazing feature to be able to set the Activity dial on the Steel HR to act as Small seconds. That is - the activity progress hand to tick every 0.6 seconds, making a full circle for exactly one minute (60 seconds divided by 100 "sectors" on the dial).
I would use that constantly even if it means taking a 50% (or more) of a battery penalty. Right now I use a Steel HR for daily walking and sleep tracking, and since I walk more or less the same every day, the Activity dial is not much of a use for me.
As to the ScanWatch - its overall design with the "real" crown on it begs for a small seconds dial. It would be even more impressive if this new ScanWatch (or any other future watch) be able to have 200 "sectors" on the Activity dial (not necessarily marked), thus being able to "tick" every 0.3 seconds when acting as seconds indicator.
I realise that having the Activity dial act as seconds would mean that there will not be a good match of "number of seconds" vs "markings as percentage" and one would only be sure of the seconds count only at 0/15/30/45 positions (100% / 25% / 50% / 75% markings on the dial). But still, it would be a nifty feature.
P.S. I found one brand that even marketed as Slow running watch (at 7200 vibrations per hour). If the Activity dial "beats" every 0.6 seconds, than Steel/Scan watches would "beat" that :-D