No - he/she is referring to SCQ as posted.
Nick - I think the answer must be that some obstruction on the airfield falls into the g/a cone for CATII (before the threshold) but not for CAT III over the threshold, and thus a low g/a hradient might compromise clearance - hence the higher minimums.
No effect on CATIII but you should have somewhere in your company OPS manual a max wt for CATIII approaches which I believe requires a 2.5% gross gradient?
Where two gradients are quoted (as for your CATII) a lot of airlines stipulate you must use the 2.5% UNLESS the company airfield brief contains figures for the higher MACG.
The 'great unknown', of course, is if you g/a at, say 199ft radio at SCQ on a CATIII at max CATIII ldg weight (to give a 2.5% MACG) what will you hit?