- I hope I have read this right, apparently with inside information, our host seems to describe the experiment as just an exercise in breeding bugs that are better at eating glucose, and they are.

That is a gross oversimplification of the experiment, and completely misses the point. The point of the experiment was to demonstrate whether evolution is constrained to a single path. By tracking the evolution of 12 genetically identical clones* in separate but identical environments, they were able to test that question. The ability to metabolize citrate represents a spectacular confirmation that evolution can take multiple paths, but it is not the only result that confirms this.

*except for a marker demonstrated to be neutral in the experimental environment

- It does seem hard to say that no other bug got in from outside the experiment and transferred some useful gene for swallowing citrate to the lab bug population – but apparently it is a combination that has never been found in the great laboratory, the natural world. Having said that, it may be a combination that is not advantageous in the natural world, only in this strange domain of glucose and citrate.

They tested in a great many ways to make sure that nothing got in to contaminate it. While it is not an absolute certainty (no conclusion in science is), they can make that claim with greater confidence than a DNA “fingerprinting” lab could claim that your mother is in fact your mother.

- I hope I have read this right, apparently with inside information, our host seems to describe the experiment as just an exercise in breeding bugs that are better at eating glucose, and they are. That some of them now eat citrate came as a surprise. Better hope they don’t learn to eat glass, or they’ll break out and escape from the lab, leading to catastrophe for spectacle wearers everywhere and the collapse of civilisation (Notice how many leading world politicians wear spectacles…)

- It does seem hard to say that no other bug got in from outside the experiment and transferred some useful gene for swallowing citrate to the lab bug population – but apparently it is a combination that has never been found in the great laboratory, the natural world. Having said that, it may be a combination that is not advantageous in the natural world, only in this strange domain of glucose and citrate.

- Another point about the natural world is that E. coli apparently has been evolving there for way longer than in -this- laboratory. (Although in this laboratory it has surely mutated every single gene it has.) So a mutation that improved glucose digestion -without- impairing uptake of other materials surely would have appeared -already- in the natural world, and would have beat out the rest. So that hypothetical mutation is already present in the initial sample after all. (Unless it’s a very unlikely mutation even on the historic scale – and then it won’t happen in your lab, either.) It only remains for the laboratory bugs to find ways to use glucose better while sacrificing other processes that are important to their cousins outdoors. For instance, if the metaphor applies of the microbe having slots in its skin to take in particular shaped molecules, like a child’s block toy, then one improvement is to have more glucose-shaped slots instead of some of the other shape slots – sacrificing (partially?) the ability to use those other molecules.

The key concept is that the bacteria changed from not being able to eat citrate to being able to eat citrate. No one, not even Larry, doubts this.

If this can happen in the lab with or without a bit of prodding from the experimenters then it can certainly happen outside of the lab.

Whether your world view can grow to encompass this new FACT is an entirely different story. Shooting the messenger doesn’t help.

“He could clarify his statements by saying that Cit+ evolution was one of several goals or was a longshot goal or a secondary goal or was never considered or whatever.”

Did you miss it?

“or was never considered”

He did say it was never considered, when he said that Cit+ was not a goal. So, he did clarify his statement, and your comment is both stupid and meaningless. He is not being evasive, you are being willfully ignorant.