In my opinion, that is what he is wearing because the top front hair bears no resemblance to the rest of the hair. Although this look is popular now, I'm pretty sure it was not around in the 1920's.

[This was known as the "military" hairstyle, popular in the late-teens and into the 1920s. For example, these guys from a 1917 Maryland college yearbook. -tterrace]

Who does his hair?

I wonder if the "extra layer of protection" is an Extra Tall undershirt with long hem or tail? Some American football players are sporting this look right now, possibly because their pants are "see thru" when soaked by sweat.

West Point used to issue those but the year before I entered science discovered elastic and garters became obsolete. My class was issued them nonetheless, and they remained an item of command interest during wall locker inspections throughout my four years.

Suspenders to keep his socks up in the days before elasticated tops.

[Those are called garters. -tterrace]

In the US maybe, in the UK and probably New Zealand they are called suspenders. Divided by a common language:-)

It looks like he already has two pair on! My Mom always told me to make sure that I wore clean underwear in case I was in an accident, but this is a bit ridiculous.

[The world was not ready for the see-through look quite yet. -tterrace]