This would be how things seem to work....

The basis for the anon proxy would be that the proxy would be configured to keep no logs, thus making retrieving something that doesn't exist impossible. However, that which seems impossible would often be possible if implemented by those with the know how (which would be the U.S. Government, which designed and implemented the tcp/ip protocol, and 'has ways of doing things' we (the public) are not aware of(as was explained to me by an information security manager @ Ft. Knox).

The alternative would be using so-called anon proxies that were located outside the legal jurisdiction of the entitiy you were trying to evade. By this, I mean, if you were evading, say, a certain countries gov., you would want to use an anon proxy that was located somewhere the certain gov. was not welcome (say, an enemy or rogue nation).
If this were done via several randomly linked proxies, and bounced off satellite connections, and all of this encoded and such, well, it would be very difficult to be 'traced'.

However, if you implement a 'handshake' with any machine, there is always the 'remote' possiblity you would be captured.

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I don't advise doing things on a computer you wouldn't mind 'the government' knowing about.

There is, however, a 'time and place for all things under the sun', so if one were to implement these techniques whos' concepts I vaguely recognized, one could be reasonably assured of their effectiveness.

OverandOut.
comJo