It may not be true for you when you have your CPU undervolted and underclocked. Any chip, delided or not will jump 40C at the drop of a hat when put under load.
Menial tasks like surfing the web and the fans would ramp up out of nowhere from 400 rpms to 2500 then back down again........repeatedly and had the same result with 3 6700Ks. Search the web and you will see this same scenario literally thousands of times across every enthusiast forum out there. How to fix it? Use a different reference that doesn't move so drastically.
and I would ask anyone who claimed otherwise to post up a video showing their CPU temps and fan speeds as Id have to see it to believe it.
In short... my suggestion to you is that if you set up a "flat" fan curve up to about 50 degrees or so [you choose] then the fans literally "can not" change RPM while surfing the net like you describe. It would be impossible. Mine is set up to 40 CPU temp which is roughly 50 Core Temp. From that point, under load, the fan RPM increases. There is no reason at all to have you fans ramping up at low temps. Any brief temp peak, as long as it's not ridiculous, is unobjectionable and wont cause CPU degradation.
Set up a spin up and down delay too.
YOU have full control over your fan RPM, so the phenomenon you describe is easily mitigated.