Possible problems:
The script is remounting your ext3 fs if you have
it as noatime. Also configuration of rsyslog is
changed to not sync. hdparm is setting disc to
minimal spins but without use of tuned daemon.
Bluetooth will be switch off.
Wifi will be switch into power safe mode.
Usecase:
Safe extra energy on your laptop or home server
which wake-up only when you ssh to it. On server
could be hdparm and sysctl values problematic for 
some type of discs. Laptops should be probably ok
with these numbers.