Sounds like the old JBL 4311 studio monitors that when they stood upright the woofers were on top. The only problem with flipping speakers upside down is that you’d interfere with the tweeters output and dispersion which may not give you a good soundstage for one thing..interesting though. For near field listening it may be fine though. Worth a try.
odd question about stand-mount speakers
Is there any reason you shouldn't turn stand-mount speakers upside down and listen to them that way, as long as you use some kind of vibration control/decoupler between the speakers and the surface they're placed on? The reason I ask is because, at least in a near-field setup, I would think having the mid/woofer ABOVE the tweeter would enhance image height/size -- assuming the tweeter is kept at ear level. (A couple of asides: I don't currently have bookshelf speakers, otherwise I would experiment. Will likely be buying some in the near future though. Also, I know that there are some stand-mount speakers that place the mid/woofer above the tweeter, but the vast majority do not -- most of the ones I'm interested in do not.)