Thanks, Melarnos and Andrea, and you're welcome.
Andrea, I guess you have to remember how far down the scroll bar goes, click-hold drag the bar to that exact spot straight away then straight back up again if it's all good and green (without letting go of the button, that should be quick enough). I wouldn't be using the scroll wheel if that's what you're doing, that's way too slow – unless you have fantastic reflexes and you're incredibly adept at using the wheel's clicker!