it is no longer recommended to cut ANY part of the victims climbing system. They can be safely lowered on their own friction hitch.
Ideally yes. But I can envision some scenarios where cutting the bridge and lowering from the ground could be the safest, easiest options.
If you have an injured or unconsious man stuck in a hot tree, sending up another climber may be impossible. Cutting the bridge and lowering from the ground could save a life. But obviously, that's already a very stressful situation, so making the wrong cut could easily kill someone.
If the rescue knot is tied in the bridge, it helps identify where to cut, or as already noted, use a bridge of a different color than the lifeline.
An option to allow a climber to be lowered from the ground without making any cuts in his/her climbing system is to use an adjustable false crotch as the TIP. Then if something happens, the climbers whole system can be lowered with the adjustable false crotch from the ground.
Also, even though all of us knows we shouldn't, I'm sure there are times when we go up a tree without someone there capable of rescuing us. I know I do sometimes. Having someone who's capable of cutting the bridge and lowering a climber could be the difference.
I've done two practice aerial rescues, both low altitude, around 20'. The first time I connected the "victim" to my gear, and lowered us both on my rope. The transition from his rope to mine was difficult and slow. Coming down with nearly 400# on my taughtline hitch (long since retired) was not smooth or easy either. I could do it much faster now, but that try took just under 5 mins, putting on gaff and saddle, climbing up, tying in, transfering victim, and coming down.
The second try, put on gear, climb up, tie in, grab the victims friction hitch, and lower us both. By far easier, and back on the ground in less than 2 mins. This alone is a great reason to never be working without a lifeline tied in and ready to bring you back to earth.
The crew I was on was the only one which did ANY practice rescues, and a buddy of mine kept working there for more than a year after I left. He said it was discussed during EHAP day, but that none of their crews had actually done any practices.
From my limited experience, I can tell you that even a practice rescue is stressful, and more difficult than you'll imagine it. Everyone who may someday need to rescue someone from a tree should give it a practice run or two.
my 2 cents.