Tootler, and others, there is not a correct way. And folks that close their eyes, are not, IMO, being impolite. It is simply their style. Others prefer to look straight at the audience for everything. Some prefer to look above the audience. Some, like myself, will use them all during a performance. For me, it depends on the song and the effect I am looking for. I think what betrays you is your training. I would not close my eyes if I were lecturing. But if the lecture included a song, I might very well close my eyes to sink into the song. This is not an oral presentation, it is a dramatic performance. We are not delivering a speech, we are singing a song. I am sure there are many overlapping "rules", but I think you are off on this one. No offense intended, just my opinion, for whatever it is worth.

All the best,

Mick