Unfortunatly it is avoided:

BusyBox v1.10.2 (Debian 3:1.10.2.legal-1osso30+0m5) built-in shell (ash)
Enter 'help' for a list of built-in commands.

/home/user # kernel-config load underclock
loading /usr/share/kernel-power-settings/underclock
successfully loaded.
/home/user # kernel-config show
current kernel configuration:
current frequency: 500
supported frequencies: 125 250 500 550 600 720 805 850 900 950 1000 1100 1150
min. frequency: 250
max. frequency: 500
avoid frequencies: 125 250
active frequencies: 500:38,360 550:38,400 600:45,430 720:48,430 805:54,500 850:54,520 900:54,600 950:54,600 1000:60,600 1100:72,600 1150:72,600
SmartReflex VDD1=1, VDD2=1
governor ondemand: ignore nice load= 1, up threshold= 95, sampling rate= 300000, powersave bias= 20
/home/user #

The Same with the profile overclock. But there it is OK for me.