When I have time to attempt LDing, I always do WBTB and some form of WILD (WILD, DEILD, etc.). However, I know what works well enough for me that I am usually back to "sleep" or in rem atonia quickly enough that I do not even think about having to swallow or scratch an itch. If I do do it, I don't notice. I learned a long time ago that what's important is being comfortable and being able to get back to sleep and not holding completely still. Remaining conscious while falling back to sleep is a nearly unconscious process that one must train themselves to learn and making a conscious effort to stay, well... conscious, but somehow let your body go back to sleep almost completely defeats the purpose or is nearly akin to purposefully setting yourself back. Go ahead and swallow or scratch that itch, it will only help you.