Part of the problem with this point of view is that you are anthropomorphizing a natural process. Calling it 'toothless', saying it has 'tools', that it 'gives opportunities, that it 'created' something that it has to 'deal with', saying it 'eats' itself...
If an acidic substance burned through a container onto a floor that it could not burn through, would you say that the corrosion had foiled itself? Of course not. The corrosion does not 'want' to burn through substances, it does not have a goal. Evolution does not want to create or change species, it has no goal or direction, it is just a force by which other things happen.
If a falling acorn lands on the ground, do we say that gravity is foiled because it's not falling any more? Or does gravity keep working on the acorn, albeit in ways much less noticeable than during its sudden descent?
Crude analogies all, but I hope you get my point.
Yes, I do get your point (in fact, it was my very first objection to my own "theory" when it came to my mind).
Let´s say that all those wordings you criticize are indeed inappropriate.
On a side note: I don´t think it is uncommon even in science to use wordings that make it sound like there were intentionality behind nature´s processes, even though it´s perfectly clear that there aren´t. If, for example, medicine explains allergies as an overreaction of the immune system (or, on the other end of the spectrum, postulates the immune system to be failing in certain cases), these wordings imply that there were some way the immune system is intended to work.
My question is: Do you - behind all those distracting, naive or overdramatizing wordings - see the point I am actually making (or better: the question I am actually asking)?
Let´s for example replace "Is evolution eating itself?" by "Do we have to update our concepts of evolution?" or "With humans having evolved in the way they did - has evolution (formerly conceptualized as the dominant force behind the development of species) lost this rank to the intentional manipulations of nature performed by one single species?" (Granted, no matter how drastic those intentional manipulations are - other species will still be doing what evolution describes...this process just might be rendered ineffective in view of the intentional manipulations.)
Even if scrutinizing my thoughts on the matter critically, I can´t detect this naive anthropomorphic assumptions that you see in them. I am not assuming that evolution is an intentional force.
Au contraire, I am asking if the mechanisms of this unintentional natural process are possibly overriden by the humanity´s ability to manipulate environment at a speed that this natural process can´t keep up with.
I don´t think that your analogies are really good ones, sorry. Gravity, for example, is a physical force, and - most importantly - a constant one. The theory of gravity doesn´t describe processes or mechanisms. Whereas evolution theory (if I am not entirely mistaken) is all about processes/change ("evolution") and its mechanisms. If an acorn lies on the ground, this is perfectly explained as a consequence of gravity.
But, for clarification, let´s start somewhere else:
A biologist studies the evolutionary changes in a certain environment for years or decades. He can explain what he observes perfectly in terms of evolution. Now, at some point, a natural disaster occurs which causes immediate dramatic changes in this environment (like, some species are completely eradicated, others lose all their food competitors, etc.etc. You get the idea). Wouldn´t this biologist say something to the effect of "All evolutionary processes in this environment have suddenly been interrupted due to a sudden (non-evolutionary) change"? (This, of course, doesn´t mean that evolution has come to an end or something.)
Now, let´s hypothetically assume there occured natural distasters of various kinds in this place every month or so. Wouldn´t biologists be justified in saying that evolutionary processes there are rendered "toothless" due to the fact that extra-evolutionary forces don´t leave them the required time to take place? [Again, this is not to say that evolution has come to an end or something. The force is still present, it just can´t work effectively (and by "working effectively" I don´t mean "working towards a particular assumed result"): An environment that changes dramatically in short order doesn´t allow for species to effectively adapt to these changes (and, if I am not entirely mistaken, this process of adaption is what evolution theory is all about).
What strikes me as remarkable and a first, however, is that human intentionality coupled with the powers to manipulate environments as dramatically as natural disasters do is not an extra-evolutionary force, but itself the result of evolution.