How did Dan never think to try his robot arms on the barricade or hatch for 6 whole years? He knew they were strong from the mountain climbing SR way back when. And if you say it's because human beings are illogical I'm gonna mail you a copy of The Last Jedi as punishment (inside joke; sorry).
Also who cuts their hair? No, nevermind--that is me being genuinely pedantic.
Er, anyway, interested to see where the leave/stay schism goes. I'm liking the developing split between the two main characters thus far.
~TAF, curious for the sake of verisimilitude
Spoiler Alert!
I knew I should have put in a hair-cutting scene. Bigga mentioned it too, but I thought, 'Nah, it isn't important; no one else is going to notice that.' Silly me. Just assume the soulborgs have some efficient method of cutting hair - either a machine of some sort or a chemical which actually halts the growth.
As for Dan not testing the Barrier before now - and I think Bigga mentioned this as well - it's because of two things: how Dan was raised, and his gloves. RR told him that the Barrier would kill him if he touched it, and because he was so young at the time, he accepted that as fact. Then he tested it, found out that it almost did kill him (as well as finding out that he could never get past it, thus eliminating it as an avenue of escape in his mind), and was left with his gloves, which reminded him every day of what the Barrier had done.
Then he realized how strong his gloves were. Before, the strength of his gloves had been relegated to the SR Unit in his mind. With his schedule, Dan had no cause to test them outside of the SR Unit, and simply associated their strength with the SR. Eventually he would have realized that their strength was not part of SR however, and chapter fifteen is just where that happened.
As for the Barrier: Dan was very wary of it, remembering what happened last time. That's why he didn't wholesale just punch it outright, but put his hand close to it first, to test it. When he felt nothing, and remembered what he had felt before he had his gloves, he knew something was different. That's the only reason he tested it.
Probably not the strongest reasoning, but it's plausible if nothing else.