I can easily imagine a couple of steeply rising trends on a decadal scale between now and 2100 (after all, we had 2 of those in the 20th century), but those still only gave us an overall temperature trend of around 1 degree or so.
(i) Were there any tipping points last century? If you want to argue that the two major rising trends over that period were tipping points of a sort, that's fine. But it means you'll have to explain WHY tipping points going forward will, of necessity, be many times greater than those experienced to date, in order to reach that 3 or 4 degrees "prophecy" by century's end.
(ii) On the other hand, if the tipping points are to be of a magnitude the likes of which we have not yet seen, that's also fine. But you'll have to explain HOW you arrive at those magnitudes.
