I assume that you are referring to the “punctuated equilibrium” branch of evolutionists? In my estimation, these types are merely abandoning some of the more untenable propositions of Darwin but still clinging to the rest of his flawed theory. No matter how many limbs they lop off, the patient is still terminally ill!
Not only them.
When I read the Origin of the Species ... (it's a long and interesting title), I was struck by how much Darwin emphasized an evolutionary process that was very slow and uniform. It wasn't just a detail of evolution, it was the essential nature of the evolutionary argument. At one points, he says that rapid evolution would be indistinguishable from a miracle.
Then Gould and Etheridge came along with their rapid evolution theory. Is the difference just a non-essential detail of timing? Or is it something more?
Let's say that Darwin's hangup (if you will) with slow evolution is not central to the argument. (That would put one at odds with Darwin, but a modern evolutionist would say that's O.K., that's just how science works.). Still, there are implications. Darwin admitted that the fossil record did not support his theory. But he thought that, in time, new discoveries would prove him right.
Doctrinaire evolutionists simply say the evidence supported Darwin. Gould and Etheridge admitted that the evidence still did not support Darwin's slow theory of evolution. They came up with rapid evolution with smaller populations. By their theory, we wouldn't really expect to find transitional fossils.
It seems that Darwin's original theory has not been supported by the evidence. The punctuated equilibrium theory of Gould and Etheridge is a theory that protects itself from the evidence.