Confirmed.
It just diminishes the bright lights in the mirror, leaving the rest of the field of view relatively undiminished.
It also includes a vibration damper, which at certain speeds seems helpful
Think it will be very good on my Spider.

Not that its driven that much after dark, but when it will be better than turning the whole mirror down and then trying find the best setting.
The main benefit will greater rear-visibility at any time.