Massive defoliation will likely lead to a huge metabolic shock to the plants, resulting in possible trichome loss of quality and slowing down final maturation too. Personally, I believe defoliation is really bad for plants and should be avoided at all costs.
For best results and peak quality, I would just leave them be to do their thing with as little stress as possible.
Trying to magically make lower buds do something special this late and this close to harvest is pointless, there just won't be enough time and if you wanted to do this, it should have been done before flowering commenced.
Let them be......stress free and happy and accept your harvest for what it is and not worry about "what if".
You are going to harvest plenty, freaking them out by defoliating and hoping to get a couple of extra grams is futile.