Not necessary.. There's a dead man's switch, or in this case dead girls switch..
Unless pressed every day at a precise time a small amount Of C4 will ignite.... It may annoy the neighbours but I think I'll have other things on my mind at the time... Or not!
I agree... Some may say overkill but you can never be too sure... Plus the neighbours should survive... They're not normally home that time of day... Normally