Mass, they're right about the numbers not corresponding to "drips per minute" and on mine, if it's set to number 1/2, none come out at all.
It's worth upping the regularity of the drops in wet weather- oil like that in a scottoiler is more likely to wash off than chainwax and similar lubricants.
Also, to see if it's working, as well as leaving the engine running (bike on side stand, in neutral) and looking, just check your back wheel (the actual wheel-not the tyre- shouldn't be any on that
). There's likely to be black flecks on it from chain fling if it's working.
I check mine reasonably regularly, not only to see if it needs refilling, but also to make sure that the level is going down (ie it's dripping).