Speed bumps have proven to be undesirable tools in many situations. For instance, it is often the case that motorists will increase their speed after a speed bump to make up for the time lost because of the speed bump.
In this situation it's fairly irrelevant, as it would serve to slow down drivers approaching and within the intersection - a few mph faster afterwards is far less likely to come with a butcher's bill than continued high-speed crossings of the intersection.