I can't tell if it is intentional or not, but it gave me a lot of headaches. I had to load the file directly to get this to work, and had to reference the property directly, because the property is not enumerable.

In order for this to work better, and be auto-detected, the enumerable property should be set to true for these properties. Otherwise the experience given by helpers.markdown() is very awkward, since it doesn't give you anything.