I say that Doby's quip can essentially mean, "No essential or basic feature of biology can be made sense of except under the idea that higher life forms ultimately are the biogenetic descendants of lower".
Therefore, given merely the verbatim of the quip itself, it is not self-evident that Doby meant a hyperbole at all.
And if I believed that the origin of the various levels of life forms is from biogenetic progress of life forms, then I would not mean any hyperbole by saying, 'Nothing in biology makes sense except in light of idea of progressive biogenetic change.
But, as long as we are dealing here with logical nuances, I would hope that it is agreed by all here that there is a genuine, and important, distinction between a species' biological acquisition of:
(a) an effective improvement in regard to a specific narrow challenge,
(b) an actual improvement in over-all adaptability potential
This difference can be clarified by how it is instantiated in familiar, comparatively very simple, non-biological systems. In such systems, a case of (a) is very easily understood not to necessarily be a case of (b). Moreover, in such systems, it is easily determined that many, if not most or all, cases of (a) are in fact not cases of (b), but are, rather, the opposite of (b).
Take a brand new, standard four-part pencil. It has a certain finite set of possible uses (not just pencil uses, but all possible uses). That set is determined by the four materials and the shape they each have: Wood as long hexagonal linear, graphite as core round linear, rubber as stubby round on one end of the wood, steel as thin-gauge, short band holding rubber to wood.
Only when the rubber is all gone is the rim of the steel band fully exposed for, say, some serious scratching usage. For instance, say the pencil's environment does not include any of the kinds of surfaces that easily bear a graphite mark, but does include an endless supply of surfaces that easily are scratched by the steel (but not easily scratched or impressed by the graphite or the wood).
Yet the loss of the rubber has decreased the the pencil's usage potential.
The loss of the rubber has resulted in the addition of a "new" usage. But that "new" usage was already there in potentia, and is realized only with the loss of information.
A slightly more complex example would be, say, a standard electric motored circular saw. If the entire saw assembly is disassembled, the total number of uses for the total of the individual parts is far in excess of that for the whole saw. But this disassembling of the saw has resulted in a very great decrease in the total power available for a given task requiring cutting.
Indeed, even though a single atom has far great power than can be applied by a hammer, the most important tasks of the hammer are not the trivial ones that are being accomplished by the countless atoms that make up the hammer. Take the hammer head off the wood handle, and you have two different tools, but neither of which is very effective in hammering nails all day.
And a box of cereal (the kind that has no airtight plastic bag inside) may make a great very temporary flotation device of the sort that, in a sewage pool, is needed only very temporarily. But, in principle, that box of cereal is far better used to keep from starving to death---as long, that is, as that nutritional use actually is employed, and not left in a meaningless abstraction of the verbatim. For, a sign on a public bike that says, 'This will help you get where you are going' is not realizable by simply hauling the bike around over your shoulder on the belief that the bike is some kind of talisman.
So, in order for us humans to access the power of the atom for important tasks, a whole lot of information must be applied. There is no information needed to wear down an eraser. In fact, for its ability to erase information, a truly most crucial kind of information can simply be erased by the unknowing wind-blown sand. The biological organism must be equal to such trivial forces, and in the exact kind of informational way by which its own proper total potential is maintained.
So if I have no hard sharp point, but I need one just to stay alive, I can break my arm, compound, so that the raw bone juts out with sharp point. But then my arm is broken, compound. This is not progressive biogenetic evolution. So the question is whether such evolution exists at all, not whether it can be imagined to be witnessed in action.
...And until such evolution actually is witnessed, other sense-making is already available for basic biological facts (including long dead, and often fossilized, biology). Yes, the complexity of other explanations may be unappealing. But I presume that you have to admit, at least, that (a) is not necessarily (b).
"Changes to the program that questions everything."