I'm glad you brought that up. I know for me, I tend to get focused on fishing and at times can become completely unaware of somebody approaching me. On the upper and middle Patuxent it can really give the sense of being away from it all.
I kind of assumed you are a big guy by your name. If it was "Tinyjim" we would know you're a monster.
I am a long haired,tattooed,bearded biker kind of guy. I'm not a big guy but fairly stout in build. I've been told I can be intimidating. So I guess I may miss some of that. But I can definitely see how some of the guys I see on trout streams around here could get taken pretty easily. And certainly worth staying alert.
On the Patuxent Specials... I have tied them fairly large, up to about 3"-3.5", and done quite well on many species. They fish well in the tide water also. The little changes I have made is small barbell eyes up at the hook eye so it rides point up. The other thing I have done is after the tail is tied on I tie in two hen hackles (normally ginger,but have used barred buff or whatever is laying loose) so they are splayed out. Looking from the top it would be shaped about like the center of a peace symbol except with the tail shorter than the "claws". I can make them swim just like a real crayfish. That little extra action from the "claws" and the front weight seems to get a few more takes. From the pics of your flies you've posted you are a much better tier than I am. You could probably do a much nicer looking one than I can.