Can a funnel be two-sided?

We often hear about the sales funnel, which moves customers from leads to prospects to buyers (and, with the advent of freemium, often contains different, and more levels) — but it would be more accurate to think of a bow-tie funnel, as suggested by In the Know.

In Customer Success and Support, we focus on the right side of the bow tie: turning new customers into adopters (with onboarding programs), then loyalists, advocates, and eventually brand ambassadors (by delivering a great customer experience), which in turn fills the outer edge of the sales (left-hand side) funnel.

Does your organization use the bow-tie funnel metaphor? Please share in the comments.