Martin,
You are a good sport and I hope you knew I was "teasing you". Kidding aside, I actually don't listen to much Metallica......but when I do it must be loud! That goes for any music that should be played loud. Veruca Salt at 80 dB just doesn't cut it, Neither does Suzie Q. at 80 dB. Norah, Allison ? Well, no need to have them scream at you, 80 is fine. I figure any "real" Hi Fi should be able to play "real music" at 100 dB peaks, at the listening spot, as measured by a typical SPL meter. I would not think you would want your speakers in corners since they were not designed to take them (corners) into account in the overall response you were trying to achieve. I have not found "corner placement" to be a "good thing" unless the speaker was designed to use them and it's overall response was "tailored" for use in corners.
Just for kicks....in a BR the woofer cones are at minimum excursion at port tuning (a good thing)......or so I thought. What happens below port resonance? Does not the driver become "under damped" and "kind of flop around" (a very bad thing for a single driver speaker)? And if the content you are listening to has significant output below port tuning (common) wouldn't that cause excessive excursion and maybe even limit SPL (due to audible distortion) in a single driver speaker? Is my understanding of this wrong?
Ed