Little Festo - Nup! Won't do it. Only something that will overwrite (many times) everything on the disk will do the trick or physically destroying the platters not just the hard drive case.
True, most of us don't have anything very important on our hard drives (apart from credit card numbers, passwords, banking info. etc) and just making the drive unreadable on any normal computer makes the job of getting the info very difficult. However there are some people 'out there' who thrive on challenges like that, and, having put all that effort into finding the info think they have earned the right to use it.
They get their kicks their way, I get mine making life totally frustrating for them!
Happy Hammer - even that isn't perfect - really smart gear can (sometimes) find the old data under the new. That is why new garbage must be written many times. All 'ones' then all 'zeroes' over and over again.
Cheers