It IS relevant when you have only 2 blocks created in 40 minutes (like right now) and a merchant that requires at least 3 or 4 confirmations.
A payment processor will cover this. You send the money through them and all is good.
That won't work. A payment processor would just destroy the underlying philosophy behind Bitcoin. A cryptocurrency is supposed to carry out the transaction without third party intervention. In other words, peer to peer. If we employ a payment processor, we are destroying these characteristics of Bitcoin.