I would happen to agee with Bill about the wooley substance, I am not sure where you live, and it might be something we don't have,or get here in florida... but as far as the flowers, what I was getting at with the teas, is that, we grow them in the full sun, deep bonsai pot, with a normal soil (non-bonsai), and plenty of water/humidity, they are very vigorous. The flowers that are here today are gone tomorrow, perhaps because of the full sun... so, they take very little away from the tree... now with the dwarf variety, they will not only flower, but produce berries, of which I've be told oolong tea is made from. Now I could see where with the berries and the flowers, they might take away some more of the energy. See where the problem lies with these trees, is often they again face the dreaded " I'm an indoor plant " story. Which just zombifies the plant, it's lethargic, best remedy get it out of the house, and slowly into the light. Everything every taught in chinese/japanese bonsai culture, says do not keep a plant inside for more that 2 days, which I beleive to be true as well. Now, I understand in severe whether ok, but I feel part of the prob. is that we all like to have plants that some times don't do to well in our locations, ie. I have some jap. maples that keep burning in the sun.
Now as far as defoliation, this I would only do on a outdoor tree, I have resorted to defoilating parts of a tree to help premote growth in other areas, but because of the old age of the tree, was reluctant to doing the whole tree. Removing the top, where it was most resilient forced out the desired new growth lower in the tree, and it didn't skip a beat.