I have trimmed limbs before off a ladder (not one inside a FEL bucket) but gave that up when one twisted around and hit me and the ladder and down we came with running chain saw in one hand. I was lucky that I just slide down with the ladder and landed on my feet but I was only about 8 feet up, not 30 feet like in your photo. No more trimming from a ladder for me. Now my trimming is done from the bed of my Kubota RTV with my brother in law driving me around. I can reach just about any limb needing trimmed with my saw. If I need to go higher we break out the pole saw. Most of my trees seem to grow limbs toward the ground so about every 2 years, we have another go around with them so they stay up off the ground with enough clearance to drive any of our tractors under them. I also think trees look better when trimmed up about 10-12 feet off the ground. I really don't need to trim any up as high as you were trimming. If limbs are hanging low from attachment point that high, I just cut off the end of the limb at some point about 10-12 feet in the air.