speaker/stand, couple or isolate?

I can only summit my personal experience and final results as I stumbled into my best setup. My speakers are Wilson Audio Sophias (160#) , my flooring is a floating wood floor on a concrete slab. After spending 6 months with the setup I was looking for a means to easily slid the speakers while adjusting the placement of the speakers in the room and purchased a set of the Herbies Gliders to assist me, spent the next couple of weeks fine tuning till I found the sweet spot, after spending a few weeks in the final position I removed the Herbies and spiked directly to floor and noticed quickly that the results were better with the Herbies at which time I reinstalled the Herbies and that was 6 years ago. About a year ago we were having new floors installed so a few weeks prior I cut spots out of the flooring and spiked directly to slab, the results were good but better with the Herbies in place. YMMV. Enjoy the music.

We now have a proper way to isolate speakers, I.e., mass-on-spring. Isolating them kills many birds with one stone. It prevents mechanical feedback. It isolates the speaker and internal wiring and crossover from seismic type vibration. It reduces unwanted speaker cabinet resonance. Problem solved! 🤗 You can forget about everything else.

Upon my original reading of the OP I neglected the speaker/stand aspect, sorry about that but feel my post may still be relevant to others. 

 I'm asking about the interface between the speaker and the stand.

Right. Its all one thing.

Speaker/stand is the exact same thing as stand/floor.

Forget that trapped in his own mind Atkinson guy. It works like this:

Almost all the vibration is coming from the speaker. In the unlikely event you find this hard to believe simply place your hand on a speaker while its playing and then on the floor. Which is vibrating more? So where are the vibrations coming from, really? 

So really what is happening is the speaker vibrates like hell causing the stand to vibrate like hell-lite and the floor to vibrate like oh I don't know purgatory. Now that they are all vibrating what do you suppose happens? The same vibrations that went speaker/stand/floor now go floor/stand/speaker. Only now since the speaker is making the music you're tying to hear, any of that vibration is gonna find its way into said music.

So its all the same and you need to deal with both.

Now as to which one does what and how best to deal with it nobody here has a clue. If they say they do all that means is they're more clueless even than they know! Because you can't. No way. In order to answer that question you'd need to be there looking and listening and understanding exactly which thing is doing what. Which only you know, and therefore only you can do.

So its all malarkey, and Atkinson can go sit in a corner with Hirsch until they both come to their senses and apologize for leading so many so far astray.

All you can really do is try different things and see for yourself which combination works best. 

What you will find- in general - is anything soft or springy will tend to damp not just mechanically but musically. Attack and detail will be softened. Which makes sense when you think about it. Attack is the first sharp motion of the driver. Newtonian physics, if the driver moves one way the speaker is gonna move the opposite way. But you want that speaker to be rock solid, so only the driver moves. So you try something more firm like blu-tac, sure enough the sound tightens up because now the speaker can't move quite as much.

If you can get your hands on some BDR Cones you will find they have the best (so far as I know) combination of stiffness and damping to bring out both dynamics and inner detail without overly damping or hyping anything. But really when it comes to specific details like that my advice is no better than anyone elses. Well, a helluva lot better than Atkinson, but that's a pretty low bar. You want to raise the bar, go and listen.