Actually, besides being annoying, it can be very destructive [mean]
If you have any weak soldered joints, or sharp bends in the pipes, these can ultimately rupture, causing significant damage. Murphy's Law will almost always come into play here. The leak will likely occur where it can cause damage that will be expensive to repair. That is why most plumbing codes require prevention measures to prevent this hammering effect.
Tmf
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The only problem with common sense, is that not very many people have it, or know how or when to use it.
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Life is not a journey to the grave with the intention of arriving in a pretty, pristine body but rather to come sliding in sideways, all used up and exclaiming, "Wow, what a ride!"