In my opinion the article "Speaker Spikes and Cones Whats the point" by Dr. Jim Lesurf is very well written.
The ones here who have criticized it should realize that this article was intended for non-expert readers (e.g. audiophiles and audiophile journalists) and not for a speciality journal. The goal of the article was to explain to non-experts that spikes do not isolate (as it is often believed or claimed) but increase the coupling e.g. between speakers and floor. The analogy given for explaining this (i.e. spikes on running shoes) is as simple and clear as it gets. The ones who do not understand this analogy are simply in no position to criticize the article or understand it for that matter.
As other have already mentioned, all these vibration management devices (e.g. footers, spikes, etc.) are fine tuning devices which depending on the situation may work or may not work.
(These devices are unable to get rid of the real elephant on ones room, i.e. excited room modes - the most critical type of rezonance in one's system. Consequently, I am of the opinion that one should take care of those type or resonances first before starting to debate the benefits and superiority of various fine tuning devices.)
I apologies if I sound condescending, but I lost my patience with some of the silly arguments above. I have started to read this thread in the hope of learning something from people with first hand experience with these products ...