Maybe your singer should use two microphones, not one - on a handheld stereo bar?
Clearly I'm not busy enough, otherwise my mind wouldn't be running to such flights of fancy.
However, I was considering the situation of where a vocalist uses two microphones on stage. An example of this would be one microphone set up normally, and the other one with a telephone or distortion effect.
So the singer can swap from mic to mic according to the demands of the song.
This isn't something that would be used throughout the set, but for an occasional contrast it can work well.
Of course, you have to imagine why the sound engineer isn't saying, "Just leave it to me - I'll switch in the effect whenever you need". If a band lets you do this, then obviously they trust you to get it right. But on the whole, any band will have too many experiences of bad sound engineering to do this unless they know you really well.
So, two microphones it is then. They can be rigged on separate stands - or more conveniently on a stereo bar. Stereo bars are normally used for recording, but there is no reason why you couldn't use one on stage.
But then I thought about extending this idea - what about adding some sort of grip to the bar and making it a handheld stereo bar?
My attempts to mock up a convincing graphic failed miserably so you will have to imagine.
But I reckon it would be 'what the hell is that?' moment as soon as the singer walks with it out onto the stage.
The creative use of mic stands is an occasional feature in music performance. Here's another example for you to think about...