I can't tell you anything about Carrie's plan, but I was just thinking about vocabulary this morning while I was running, so I'll tell you what I've noticed this year in my son.
Last year my 7 yo (2nd grade) was doing Saxon phonics which goes into great detail on prefixes/suffixes...and we were doing Wordly Wise for vocabulary. We were definitely hitting this area with a thorough
drill approach.

(My poor experimental 1st born!) This year I started Bigger with him, and within a month I noticed a huge change in his vocabulary!! Just in our conversation around home, his vocbulary had changed a ton. I KNOW that this is from the great books we're reading in history, science, & storytime...and
narration! It was an obvious change that we didn't get using the workbook approach. My mother-in-law was here last week (only lives up the road..so we see her a lot), and she popped in while Grant was narrating for storytime. She commented how she just can't believe how well he retells things and he uses great vocabulary.
All that to say that I believe the narration that's a critical part of a CM education does wonders for a child's vocabulary! The vocabulary box in the guides does probably teach the child new words, but I see that time as more of a tool to help them gain skills for learning what an unknown word may mean, using a dictionary, alphabetizing.

Kathleen