How does percolation help make a hit smoother, and does this make some percs more efficient than others?

The more percolation the more the vapor or smoke comes into contact with the water.   The more contact that happens the cooler the vapor or smoke becomes, as well as filtered.  The more bubbles a perc makes the perc more efficient, but that is with a catch.  If the holes are too small, they clog more easily.