Effects of different feet on floorstanders with a thickish rug

Are you asking about a concrete floor with various things on top of it or are you comparing a concrete floor to a traditional joist and plywood floor?

@n80 -- no, the OTHER post I referred to was asking about a concrete floor. I have a traditional joist and plywood floor, with a moderately thick rug over it. I don't hear much difference when I use the spikes; what should I be listening for? Is it common for people with rugs to use their floorstanders without the spikes? If so, is there anything else I SHOULD be using for best sound?

If the objective is to completely pierce the thick carpet and the underlying mat in order to achieve better coupling with cones a hole punch comes in mighty handy.

This is a debate I really don't care about. But I'm not sure what the OP is asking. Are you asking about a concrete floor with various things on top of it or are you comparing a concrete floor to a traditional joist and plywood floor?

Exact same thing.

Yeah I know everyone thinks otherwise. Well sorry, they're wrong. Wrong about the pointy stuff needing to "ground" or whatever. It just doesn't work that way. Of course you have to experiment, actually try out a whole bunch of different things to know. Way easier to repeat whatever you heard than try and compare things that seem unlikely. Which is exactly what I have done. 

First time a guy told me to put a round thing under my cone I thought he was nuts. How's the cone gonna spike into the flooring? Its gonna float! Stupid idea. But I tried it. Sure enough, way better.

Of course it matters what you use. Everything matters. Nothing is so simple. But what you asked was how is carpet different than wood, or wood over concrete, or whatever. And the answer is- it isn't.

Exact same thing.

@millercarbon -- I'm not sure what you mean; your advice in the other thread seemed to be fairly specific to hard floors.  I'm trying to determine what effect the use of spikes with a rug is likely to have on SQ. 

Exact same thing.