it does but your components life will exceed the time you will use if that makes sense. lets say the processor you have it was made to last at minimum 10 years...you wont use it for 10 years, you will upgrade by then...you overclock it and take 2-3 years away in worst case scenario...that's still 7-8 years of component life and you will upgrade before that anyways. when overclocking dont let your load temps go over 80c and you will be fine. dont overclock using stock heatsink, with good heatsinks you can re use them when upgrading as manufacturers will release new mounting brackets to make them compatible with next upcoming sockets
i dont know as I dont use that cooler, I'm personally using corsair h100 which is a water cooling setup
when ocing your idle temps will stay the same or 2-5c higher with the added voltage for stability so lets say 30-35c idle and your load should not go over 80c
Every year they release a new CPU that's faster than your current one. If you overclock, you can match the performance of that new processor. With better cooling you get more overclocking headroom, so it saves you money.