A motion to dismiss based on failure to commence before the statute of limitations expired is not a complicated one. Yes, there are procedural loopholes which may save an action, but 9 times of out 10, Mr. Plaintiff is simply screwed. When you represent a large entity which is unfortunately often mistaken for a similar but different large entity with a longer statute of limitations, you can make these motions in your sleep and calculate expiration dates in your head.
So it's amusing when you get opposition papers which yell! and taunt! and threaten! And which make it clear that opposing counsel is, well, an idiot who not only doesn't do the proper research and investigation prior to commencing an action, but who simply. can't. count. Time to go back to 2nd grade.