Limiting Calendar Token dates to only future dates.

Has anyone ever made the mistake of filling in a calendar token with a date in the past? It's happened to me before when I clone my program templates.

What are people's thoughts on Marketo limiting dates in the calendar token to only allow dates in the future?

(If this already exists, please show me, because I made the mistake again today! I was off by an entire year)

I started a poll, but I posted it in the France User Group group - if you're able to see it, please go vote.