I don't want CCleaner to just delete system files but delete them for good, being unable to recover it. There should be an option for this. Temporary files, memory dumps... all these could contain sensitive informations.
Can't you already do this already? CCleaner>Options>Settings>Secure Deletion>Enable "Secure file deletion". Or did I misconstrue your post?
Can't you already do this already? CCleaner>Options>Settings>Secure Deletion>Enable "Secure file deletion". Or did I misconstrue your post?
I assumed this setting only applied to "Wipe Free Space" option.... or does it also apply to all of the options above it?
I assumed this setting only applied to "Wipe Free Space" option.... or does it also apply to all of the options above it?
Does not apply only to free space wipe. Applies to all runs. (Except I tested and found that Free Space Wipe gets only 1 pass.)
With Normal file deletion you may be able to recover files using Recuva. Not so with one pass or more overwrites using Secure file Deletion -- all zapped.
I use single, anything more is overkill.
After zapping you can check the destruction of files using Recuva, and by ☑ticking these boxes. 
Overwritten with 000000000000.