Hi there,
there is an excellent sticky on this board about pat/shush that you should read, as it answers a lot of questions/concerns that a lot of us have had about pat/shush becoming a prop...and don't worry, it doesn't as long as you learn to back off of it when dd is ready. the goal of pat/shush is to calm them/keep them calm when falling asleep in their crib from an awake state. Over the course of time you should notice that you will not need to pat/shush as long, so you can slowly back off of the patting and shushing until eventually you lie her down and maybe pat a couple of times and she's off to sleep.
the tricky thing is though that pat/shush may start to lose it's effectiveness as the baby gets older, and since your dd is already 5 months it may not be working as well and may need to do pu/pd. this method is intended for to stay with the child the whole time you are teaching her how to sleep, and giving her the opportunity to learn how to self-soothe, ie, sucking her thumb or whatever. Once my dd turned 3 months pat/shush wouldn't work anymore so I started pu/pd and it worked excellently.
I'm not really sure if your dd needs this, but if you think she does, I suggest readign the sleep interview as well as the 2 posts by Theo's mom on pu/pd and pat/shush and then come up with a plan.
Tracy's methods are wonderful but sometimes need some tweakign to fit your particular situation/baby, so don't be afraid to do that. the key is consistency. Her new book is also an awesome resource!
Good luck!
Andrea