Evolution of irregular verbs over the last century

Solution 1:

It's difficult to find evidence for saying that "irregular verbs are dying out" overall. There are:

• a few cases, e.g. "spelt"/"spelled", "wrought"/"worked", where over the last few centuries there have been fluctuations/changes in the percentage use of the regular vs irregular alternative, with the regular alternative having ousted the irregular to differing extents;
• a few cases where a more modern use of an older verb takes on a regular form ("it cost 10 dollars"->"they costed it out"; "it was put in"->"it was input[ted] incorrectly");
• a few cases where the trend has gone the other way, in some cases fairly recently (e.g. "dived"/"dove", "sneaked"/"snuck"-- where "snuck" appears to be more recent in fact); also cf. "he hanged himself"->"he hung himself;
• a few cases where one irregular form has or is being supplanted by another, but it's probably fair to say the verb is still "irregular" overall: "he span it"/"he spun it", "it hasn't run"/"it hasn't ran"

But if you look at the language overall, I don't think the number of irregular verbs has really changed in order of magnitude over the past few centuries, nor has there been any kind of structural change overall (the overall "types of paradigm allowed by English verbs" has essentially remained the same).

Solution 2:

The Oxford English Dictionary says of "snuck": "pa. tense and pple. also (orig. and chiefly U.S.) snuck.". It gives an instance of "snuck" from 1887.

So "snuck" is an innovation, though in the US it's older than the 20th century. (Like "dove", from 18th C in the US: the first time I encountered "dove" as the past of "dive" in an American source, I was genuinely confused, wondering where pigeons came into it).

I think it's quite rare for new irregular forms to be created, though I can't point to any reference; what has happened a number of times in the history of the language is that two forms have been in contention, and the strong ('irregular') form has eventually won.

I'm thinking particularly of "dug", where you find "digged" in older texts. (However, the OED says that the past participle was always "dug", and what has happened is that this has ousted the original past. It is unusual, though to find a word with a weak past and strong past participle, so I suspect that both forms were there from the outset).

[Edited: I had misinterpreted the OED entry as saying that "snuck" was the original form.]