I see the muzzle loading section is quiet again that in a way is inviting some posting.
I often wonder how many actually apply this method to their ML activities. For me using a SML this approach is essential to avoid a possible disaster. A witness mark basically confirms if the bore has some form of a load present. The witness mark is usually placed on a ramrod. In my case I have another method that works well. Regardless a witness mark is an ally to protect from a possible mishap.
In the field there are no real distractions but before I load, I still stick the ramrod into the bore. When it sits flush with the muzzle, I’m good to load. At the range is another story when other people are present. Someone always seems to want to talk or ask questions when you are in the middle of loading. Then when you are done chatting and get back to loading you need to re-orientate yourself as to where you left off. A witness mark tells the story.