I would just take it way. doing it half way, or "only at certain" times, still allows them to buy into the idea that they get it. Kids tend to see things in Black and white.
they get it or they don't get it. And to me, giving a partial paci is teaching them about grey areas and "even though we don't want you to have it, we'll still give you the idea of it" approach still keeps it in their mindset.
sure, going cold turkey might make them be rather vocal about it at first, but after a few days of not even having the visual piece available to think about they'll move on, find something else to take it's place. Besides, what does snipping the ends off really do? they can't even suck on it, so it's just going to make them mad, because now they have this thing they want and it won't work. And it still visually reminding them of what they want.