There are several reasons why shush pat is not a prop. Shush pat is a tool to teach a baby how to sleep. You use this to teach them to go to sleep in their crib. This is why you start out on your shoulder and then into the crib, finishing in the crib. They actually go to sleep in their crib. Also you can use less or more of shush pat. You can try to reassure with just your hand and use more if needed and you can gradually use less when trying to teach more independent sleep. Itís a balance. Itís easily removed when done correctly, doesnít become a prop/dependency.
PU/PD is a last resort tool to teach sleep, usually when a prop was used and this prop is no longer working. The reason for this is that a baby wakes wanting the prop over and over again. With PU/PD you are teaching independent sleep with no props so a baby can go to sleep, back to sleep, stay asleep themselves. PU/PD isnít a prop and wonít ever be since its used differently, you donít put them to sleep with it.
Props like rocking and bouncing etc. are props because the baby requires your full assistance to go to sleep. You are generally putting them to sleep or almost to sleep before entering the crib. Often this creates the habit of waking and needing the prop to go back to sleep. There is a connection between how a baby goes to sleep and how they can put themselves back to sleep if they wake and need nothing. They canít rock and bounce themselves back to sleep. Itís also hard to gradually use less bouncing or rocking. It just isnít independent.