Double Glazing and why I hate it

My pet hate is double glazing. Not just persistent salesmen you can't get rid of, but their insidious product you also can't get rid of. For modern hermetically sealed buildings they work, but in lovely old buildings they are wrong on every front.
Look closely at the photo below, to save money an angle grinder has removed the stone mullions to wedge in a plastic window; utterly criminal !
For my next project I am going to fit a stained glass panel into a double glazed unit to give a Victorian house its face back.