The plain boss at the centre of each crest is the most interesting decision on this bed, and it is a subtraction rather than an addition. Baroque carving fills space by instinct; putting a smooth undecorated dome in the middle of it goes against that instinct entirely. It works because the eye needs a resting point - without one, dense ornament reads as texture rather than as design, and nothing stands out because everything does.
Carvers have used the device for centuries under different names: a pearl, a boss, a paterae. What matters is that it is perfectly smooth, because any tooling on its surface would make it part of the pattern instead of a pause in it. Getting a hand-carved dome truly round and truly clean is more difficult than carving a leaf, where small irregularities read as life.
Our master Indian artisans finish these bosses last, after everything around them is complete, so the shape can be judged against the carving it sits in rather than in isolation.