As I understand it, the reason why blooming was never implemented had to do with the inability of the engine to handle any more render passes than it's already doing. So, I was wondering - are the render passes eliminated by turning commandlines like -glow -spec and -env off? I just wonder because, personally, I'd be willing to sacrafice environment mapping for blooming, and since my video card (Radeon 9200) doesn't support spec anyway, I'd in turn willingly take that off for, say, bumpmapping or whatever else might need a new renderpass.
I'm probably on the wrong track here as, having typed that, it strikes me as unlikely that you wouldn't have thought of it. But worth asking, no?