More info I found in a Triumph forum:

It is programmable to 10, 20 or 30 seconds.
The "timer" does not start until you release the brake.

So in theory, you roll to a light, apply the brake, turn on your signal and as long as you hold the brake the signal stays on, your signal will go off in 10, 20 or 30 seconds after you release the brake and make the turn.

Or you roll to a turn, signal, no brake and the same as above.

The only catch is the signal switch has to be cancelled before you can use the turn signal again , no big deal the way I see it.

So I believe the intended use is more of a safety 'back up' in case you forget to cancel than a 100% set and forget auto T-SIG cancel device. Could be used either way, I suppose, but cancelling the sig manually will always be required at one time or another. Still, if it's 100% plug and play (depends on the bike) it could be an asset.