Comment by crote

"Is year divisible by four" will work perfectly fine for the next 75 years. Random consumer devices are definitely not going to survive that long, so being capable of dealing with it adds exactly zero value to the product.

It's hard to imagine being in a situation where the cost of the additional "year divisible by 100" check, or even the "year divisible by 400" check is too much to bear, and it's trivial enough that the developer overhead is negligible, but you never know when you need those extra handful of bytes of memory I guess...