I've been learning a lot about bitcoin over the past couple of weeks because I have some interesting ideas for websites and I would like to accept bitcoin as payment.
One of my concerns centers around a somewhat more advanced topic that so far I've only skimmed the surface of. And I cannot find an adequate answer to my question online.
I was reading that it is possible to program simple contracts into bitcoins to ensure that the recipient must spend the coin in a specific way, or within a specific time-frame. Here is simplified video that discusses this as a feature but does not go into the security implications of it.
Could this possibly be used to scam merchants, for instance, by returning the bit coin to the sender after a period of time, or to hold the bitcoins hostage? What tools do merchants have available to protect themselves from this type of abuse?