Quote Originally Posted by TheMetal1
I believe the purpose of drying the majority of the soil out, is to encourage the roots to grow in search of fresh water. So, when they say "wet/dry cycle," it really means wet them FULLY... and dry them until they are practically BEGGING for water.
This is true, and there is one more reason, which is that as the water recedes, air is sucked in to replace it, bringing much-needed oxygen to the root zone. Without oxygen, you get what is termed 'reducing conditions' in nerd land (a place from which I have many visa stamps on my passport hahaha), and soil chemistry becomes unfit for plant life, and only certain anaerobic bacteria can survive there.