That's news to me. HOW are they equivalent?
Prima facie ID is equally consistent with any amount of evolution and common descent, and equally so with no evolution. After all there are "design advocates" holding both position, i.e. those like Behe who have no problem with common descent, even with (at least potentially) univerisal common descent, and those like Jonathan Wells who seem to be thoroughgoing antievolutionists and quibble even with sub-species microevolution like industrial melanism in Peppered Moths.
It seems to me that -- since ID is consistent with any amount, or no amount, of evoluiton (see also my message just upthread on the vacuousness of ID) -- the question of whether or not "design events" occured is, logically, completely independent of evolution.
There is a connection but it has to do merely with the instrumental matter of detecting "intelligently designed" structures: i.e. the methods of detection suggested by IDers all amount to claiming that this or that structure couldn't have happened "naturally" (by a stepwise evolutionary process) so it must have been "design". However in this very message you explicity reject such logic (saying it couldn't have been that so it must have been this), at least when (you think) evolutionists do it, so this question of detection can't be the reason that proving ID and disproving evolution are "equivalent endeavors".
I agree that “proving ID” and “disproving evolution” are not necessarily “equivalent endeavors.” I got a bit sloppy with that claim.
The truth of that claim depends on how “evolution” is defined. As you point out, there are many variations in the meaning of that word.
However, the claim *is* true for a particular meaning of the word “evolution:” The purely naturalistic meaning. The purely naturalistic meaning explicitly rules out any and all ID, so by definition, “proving ID” is equivalent to “disproving (purely naturalistic) evolution.”