What happens when you try it?

Jethro Burns never strummed chords?

I now predominantly play fingerstyle on gut or nylon strings. But I’m also a long-time clawhammer player on steel. An ideal candidate for a blind test. 'Feel’ - the interaction of fingers and strings - has much more effect on articulation when playing fingerstyle than when playing clawhammer. No big surprise, from the basic fact alone that the pads of our fingers are infinitely more sensitive than our one (by comparison ‘dead’) fingernail.

You weren’t thinking no-one would quickly flip the tuning of those two strings out of curiosity were you?

My first superficial but relevant comment is the effect on string tension. I have to assume you’re not just swapping tuning, but that you also swap strings? On my nylon strings this morning, as I suspected, simply swapping tuning only leaves me with a (for me) too loose 1st, and - worse - an unresponsively taut 2nd. My curiosity stopped there as I’m not about to re-string.

What do you think are the positional advantages to you doing this? Thinking through it, rather than actually playing, I can't really see the point. But that doesn't make you 'nuts'; it's your banjo.

Yeah, I'm a cranky old curmudgeon. Hope you don't take any of this too personally. Apologies in advance, if necessary.

E-C# is a sixth... You mean B, right? Either way, that would have to be a VERY short-scaled banjo, or a first string of some material I've never heard of.

Anyway, it seems like you're just talking about a tenor banjo, tuned standard CGDA, with a capo on the 2nd fret. That works just fine for playing a melody line with a flatpick, which is straight-ahead Irish style. You could add a short thumb string to that, and play it clawhammer style, but IMO it would be VERY difficult to do that in any way that would be really musical, and even harder to make it fit into any existing stylistic context.

The banjo (with a short thumb string) and its traditional playing styles are of West African origin, and while we who use European-based terms to describe music can hear what we understand as a melody line and chord changes in there, that concept somehow manages to over-simplify what traditional players actually do, and at the same time make it seem way more complicated than it is.