As usual Doc is 100% correct. Perched water tables are how we used to build golf course putting greens but science has proven the gravel layer at the bottom makes things worse as far as moving water through the soil profile. If water wont move neither will air or roots. The lack of movement can be the kiss of death in container growing, also putting greens.
Hah! Listen to the pro's....they know of what they speak.
No one wants healthier "plants" than a Golf Course. Case closed! Stop putting rocks and crap at the bottom of your pots!