con law: confusion over bailey v. drexel furniture co.

[dudnaito]

The Ct. stated that a law passed by Congress under the pretext of taxation, but actually trying to accomplish another end that is beyond its Constitutional powers, will be denied. In this case, it was the regulation of age, hours, pay, etc... and there was a 10% penalty to its net profits if found that a company was breaking this law. However, isn't this virtually identical to what the Courts did in US v. Darby where they were able to regulate hours and wages? The difference being that in the latter Congress relied on the Commerce Clause. Can't Congress just be like... ok, then let's try again except we'll use the Commerce Clause this time?

Or is the big difference more the political/legislative climate, since the Bailey case was post-Dagenhart while Darby about 20 years later overruled Dagenhart?