LLC taxed as S Corp - 401(k) maximization

[Charles Allen]

So as my understanding goes, the IRS does not know what "LLC" means. It understands Sole Proprietor, Partnership, and S-Corp, but not LLC. One of the interesting options is to take an LLC and ask the IRS to tax it as an S-Corp.

"Wait, Charles!" you say... "You'll get double taxed AND have wage taxes to deal with!"

But here's my question: If one spouse is NOT drawing external income, they are not able to take advantage of 401(k) sweet tax deferred options. It seems to me an LLC taxed as an S-Corp should be able to employ the spouse and allow the spouse to contribute as much of their salary to a 401(k) as desired, ideally being able to hit the federal maximum of $55k for 2018, with employer (s-corp) contributions in there. This would allow for huge growth in tax advantaged accounts.

Would such a strategy ever make sense or would it be crazy?