Why aren't my legs encumbered?

0.C stable.

Currently wearing on my legs:

Sheath (waist)
Drop leg pouches (strapped)
Knee pads (strapped)
Duster (outer)
Leather chaps (outer)

All items have encumbrance 0 and fit me perfectly.
All items except the duster layer easily.

According to the in-game help, I should incur an encumbrance penalty for having more than one layer with an extra item.

What am I missing?

Fitting items incur only 0.5 layering penalty. Layering penalty won’t happen until you have at least 2.0 penalty on the body part.

Interesting.

So, the in-game description is out of date?

If you have three such items at 0.5 each, does the penalty (1.5) round up to 2.0?