No, there are many creatures where differences are small enough that scientists debate whether a certain branch is just another breed (i.e., dogs), or separate sub-species, species, genus, etc.
The criteria they establish for these various sub-groupings are more-or-less arbitrary and may not, historically, have been consistently applied.
That's why we can see the example of Polar Bears, once classified as a separate genus, now reduced to just another species within the Ursus genus.
That change was caused, among other reasons, by the discovery that Polar and Brown Bears can and occasionally do interbreed in nature.
Another example is Neanderthals, once classified as a separate species, now considered just a sub-species, along with some others (i.e., "Hobbits") of Homo Sapiens.
One reason is the discovery that, ahem, some of us do carry a few Neanderthal genes -- who would have thunk it, Neanderthals in our wood piles? ;-)
Point is: these classifications are more-or-less arbitrary and subject to change as new data becomes available.
So speciation is strictly, in your term, "analog" -- there's nothing "step" about it.
So IYO speciation or naming different species is a "sampling" technique of the greater analog evolution process. So Neanderthal is a sample of a greater being with traits similar to modern humans. I will consider that but I still see it as step function with species suddenly "appearing", paleo biologists use this phrase all the time.