I know this topic has come up several times, and I realize you fear "misuse" of the product. However, I'd like to address a different scenario in which spectrum matching would be extremely helpful. Lately I've been using HB to match the spectrum of tracks which have had some effect added -- in particular, amp modelers. Many of these plugins do nothing more than apply some kind of EQ/envelope. What I've been doing is matching the spectrum in HB and producing WAVs so I can disable the plugin but still have the sound I want and free up the CPU to work on other stuff during mixing.
My typical process is to dial in the sound I like on the plug, then build a WAV of the track in question and open it up in HB, then start dragging like crazy to match the spectrum. As you can imagine, this is rather time consuming since most of the time the spectrum has been changed fairly significantly by the plugin. It would be an enormous time saver to be able to automatically match the spectrum.
I hope you guys aren't still afraid of this feature. I think *any* feature in any software can be misused. It would be unfortunate to withhold something from users when it's likely that only a small number would "misuse" the feature (I'm not entirely comfortable with the word "misuse"). And I think it's extremely unlikely that an engineer would just match the spectrum of another song and be done with it, then give the finished product to the client hoping the client will think it sounds good, and then blame it on HB if a client complains about the quality of the mix. Please don't make the rest of us pay for someone who'd be stupid enough to do that!

So, seriously guys, HB can (and does) have more uses than just a mastering tool. I and many others would be very happy if you added this feature.
Thanks for your consideration,
Jay