Right. As long as you aren't mentally rehearsing all the way through later in the process. Try to get a feeling of what it is like at the beginning and at the end of your mental rehearsal. After about three repetitions, it will be way too fast for your conscious mind to process. If you try to imagine all the details in sequential order, you will go too slow. Just get that "feeling" with each repetition.
As with any behavior you want to perform, at first you need to consciously go through the process, from beginning to end. But then you want to let the neural pathways of your brain repeat the sequence, so that it makes the necessary connections. The high number of repetitions you are having your brain perform makes it possible for your brain to continue building the neural pathways on its own.
