What's the verdict on "sooner than later"?

I have heard a lot of people say at work that we should do something "sooner than later." This grates against my native ear, but it seems fairly commonplace. I have always understood the expression to only make sense as "sooner rather than later."

I found this Word Reference Forum thread on the subject. One poster gave a very reasonable explanation why "sooner than later" is incorrect:

I think it should be "sooner rather than later".

There are two choices: one can do it sooner(A) or one can do it later(B). Each one refers to the doing of "it". >For this choice:
I want this done A rather than B. (correct)
I want this done A than B. (incorrect)

The fact that the adjectives are comparatives and the construction uses "than" is what makes it tempting to remove the rather. Sooner than a specific time might work (adding in e.g. by 7pm), but sooner than (another comparative adjective) in my mind doesn't work.

However, consider:
I want this done quickly rather than slowly. (correct)
I want this done quickly than slowly. (incorrect)

I agree with him, but was also able to twist my brain around to give the phrase some kind of meaning and actually found myself suggesting ways it could be semi-correct. Here's what I wrote:

I came across this thread considering the same question myself. Below are two caveats to the excellent response by Julian Stewart, and the caveat to my caveats is that you will not find me saying "sooner than later."

It definitely makes sense to say:

"I'd like to walk faster rather than slower."

And it could make sense to say:

"I'd rather walk faster than (walk) slower." "I'd rather walk fast than (walk) slow."

And therefore:

"I'd rather finish sooner than (finish) later."

Secondly, I can conceive in some convoluted way that "sooner than later" can be used to communicate exactly what it denotes: a point (or range of points) in time preceding the point (or range of points) described by 'later.' I know it's screwy, but it kind of makes sense.

I'd love to hear what you folks here have to say on the matter and see if anyone can make a compelling and definitive argument. I fear I might have put my brain in some alternate English reality in order to make the defense I did. Talk some sense into me please?

Solution 1:

Here is a SWAG on this one. I suspect that it is actually an idiom based on analogy with the much more grammatical "sooner or later." I think that it is a transformation from "I'll get around to it" to "please do it now", and it is done in a parallel way. The parallelism requires the substitution of "or" with just one word "than" to keep the rhythm the same.

"Sooner than later" is a pretty new expression, picking up in the 1940s, though "sooner or later" is a much older and more common expression.

As to its grammatical correctness; it is certainly idiomatic and idioms seem to be allowed a lot of latitude on the grammatical front. Which is to say, "eat your heart out" Strunk and White.

Solution 2:

John Lawler has actually opened my eyes to the fact that "sooner than later" makes sense. Think about it. When we say "sooner rather than later," what we really mean is soon rather than later. So there is a redundancy to "sooner rather." Only one is really necessary. Once you become accustomed to "sooner than later," it starts to sound correct.