Hi,
I don't find these restrictions very useful and it is not clear that it will help in the end : those that want to troll just wait 4 hours and in the mean time post to this thread for example.
Better is IMHO to ban people if they don't behave : black list the e-mail they used and erase their registration. So in order to come on-line again they would have to re-register with a new e-mail address. My guess is they will get bored very soon.
The moderator could send them a warning maybe
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