Agreed Lumi.
From my experience in a tank in wooded training areas of northern Minnesota and Ft. Knox Kentucky, I found that you could go 20-30 MPH with the TC, and loader watching for things, or just the Loader, or just the TC. It is very easy for the loader to jump down prior to firing, and a skilled crew will know where everyone is at at all times. Branches are dangerous to crew outside of the hatch, but as a loader and commander, not once did get hurt, or come close to being hurt by branches. I have had crew hurt at full speed, and the story is below.
In Idaho the tank I was gunning on was retreating at top speed around 40 MPH with the turret over the back left side of the tank looking at targets (Bradley's), as we moved into the low ground and toward our defensive line. The commander was watching over the back of the commanders hatch, which you have to be kinda high out of the hatch to do, and the loader was helping to see targets over the back. The driver went towards what we found out was a dry riverbed, but was filled with sage brush. The sage was a close match to the grass around it, but was totally different from the dirt road that went over it. The commander told him to veer left, and cross on the road. The driver did not listen, and drove right into the riverbed. He slowed down but it was too late, and we hit it at 30 MPH or so. The riverbed was about 10 feet across, and about 4 feet deep. WE hit so hard that the front slop dug into the ground and left almost a foot of dirt on it. Mud flaps bent up, but other than that no damage to the tank. The driver bounced up in the seat and hit his head on the driver hatch, and was knocked out for about 20 seconds. The loader was thrown back into the loaders hatch ring, and bruised his back and ribs. The commander hit hard into the commanders hatch, and only received bruises on his arms, and a sore face, but no cuts. I in the gunners seat, was slammed into the turret wall, hitting my head (we all had helmets on) on the ballistic computer, and then was thrown towards the gun breach. I did not have my helmet strapped, and it flew off my head, and I came within inches of having my head squashed by the breach, as the gun tried to maintain on target going violently up and down. We rolled out the other side of the riverbed, and rolled to a stop till the driver was awake. We moved to our defense position, and then had to send our loader to the hospital for possible broken ribs by helicopter due to the distance from the base.
This happened due to the crew not knowing what was happening or going to happen. There was no warning till it was too late of entering the riverbed, the speed of which we entered, the position of the crew and turret, and the lack of experience or just common sense of a driver. This driver got a beat down for this and one other issue where he was unsafe where he started driving without a command, while people were on the outside of the tank (on top, and hanging on the sides doing maintenance).
With this said I agree there could be some damage to crew and components, but I would say minor ones. Maybe if there was an option to have loader out for 5 or less minutes like the radio, and not stuck getting better if you sit still, but on the move too. If a tank can take a ditch which is almost a tank ditch at around 30 MPH and not be damaged, I am sure we can hit a tree, and not get major damage to vehicle.