My swords always put out streams of bubbles after my angelfish put holes in them while they're cleaning for eggs. They wouldn't pearl otherwise and my growth is fine. All pearling really means is that you've reached optimal (or pretty dang near perfect) conditions with plenty of CO2, light, and nutrients. Some plants do it much more than othersd so it is not necessarily plant health related.
From what I've been able to discern durning my research on plant biology, pearling is just the expiration of oxygen at a rate faster than it is being dissolved into the water - it is a sign of healthy plant respiration, some plants do it more than others, and the lack of it is not an indicater of plant health one way or another.