I would add to that the fact that, if we are happy to be caught in flagrante delicto in a picturesque setting, there would be something almost humiliating about being caught somewhere as ugly as that.

Normal untransplanted marrow was used as a control to ensure the quality of the stroma and the comparability of the experiments at different times.

Thus the gradation of the direct object provides an explanation for the unattestability of [ +derived / -specific ] direct objects in the language.

This world is full of trouble! There can be no doubt of that. Nothing but bother and perplexation!