It should be straightforward and simple... the existence of any penalty points on one's normal driving licence should preclude issue or renewal of a SPSV licence.
I don't ever see that happening, but what I would like to see is fer us professional drivers to have the same Six penalty points and your Off fer 6 months, which is the same fer Learner and Novice drivers.
Currently Learner, Novice and Professional drivers have a 2ML of whatever to be under the drink driving limit, while the layman with a full licence has 5ML of whatever to be under the limit.
Why not make them both the same ?