Everyone has their take on Defoli.... I like to do it for air flow purpose and also to direct energy to the tops. I take off the lower nodes (leaves and shoots) when they are in shadows below the canopy.
I even removed upper fan leaves if they are in the way of the tops growing.
I'm trying a new way right now.... I'm removing just the shoots and not the fan leaves... by doing this, it should once again re-direct energy to the tops but with less shock... I will eventually remove them when the become under shadow or if they start to die off.
If you're unsure, just start at the lowest node, remove, wait for a couple of days for recovery, then move on to the 2nd node if needed
Happy Growing!