We have a princess flower plant (Tibouchina?) that thrived for around 15 years with regular pruning. Then for another 10 years it was completely ignored- it ended up growing out into two very long spindly trunks with the majority of the foliage way out at the ends (see pics). I would love to wrangle it back down to the small plant/tree that it used to be (contained to it's spot and not growing out over the patio). There is currently a very healthy growth coming off one of the two main trunk pretty close to the base (see close up picture). Can I simply cut that trunk away just above where that growth is happening, and completely cut off the other trunk and then continually maintain it's growth from there? Or would that be too traumatic to the whole thing?