Cannot alter MBP Power Management Settings
I identified a serious problem between power management and sleep states management
in version 10.13.4 of MacOS X (I had regular crashes on sleep and hibernate exit: around 5 times a day, and files modifications lost).
I thoroughly tested 10.3.5 and Apple seems to have fixed many problems.
standby 1 isn't anymore causing a crash on encrypted filesystem on hybernate exit and on sleep exit,
acwake 0 is working as expected.
But lidwake 0 is still not working, thus potentially causing the MacBook Pro overheating in a bag around the lower part of the screen and the upper part of the keyboard.
The DestroyFVKeyOnStandby 1 isn't yet in the documentation and causes a crash on hibernate exit.
The documentation (man pmset) isn't appropriate for the pmset command:

some options aren't documented,
others aren't behaving as documented.

pmset -g pslog is pretty useful to understand this behaviour which is changed without notice and without documentation.
I advise you to download MacOS X 10.13.5 combo update
Now I recovered a MacBook Pro I could use to work.
NB: I didn't tested 10.13.0..3 nor 10.13.6 nor 10.14.... (nothing needed, not yet a free dayfull of work to waste on tests, and no time to spend for an editor who doesn't make a correct documentation).