Title: Adding and Replacing a Key Value

Describe the issue:

The following sentence needs to be clearer in terms of what is happening, which is that the line makes jdg check for a key value, and if it doesn't find on, it uses the value specified in the line instead of the phrase "key" as the new key value and if it does find the key value, it does nothing.

"Check if the key value is missing. If the value is not found, replace the absent value with key. If the value is found, no change occurs."

Suggest rewrites.

Scope: 1 cycle.