Create CSM and TAM roles of engagement document

contents/handbook/growth/sales/csm-tam-overlay-coverage

@@ -0,0 +1,60 @@
+---
+title: 'CSM + TAM rules of engagement'
+sidebar: Handbook
+showTitle: true
+---
+
+Some accounts have both a CSM and a TAM. The point is depth: two people sharing the load so each can focus on what they're best at, and the customer gets a better experience than one person stretched across everything.
+
+Both roles have a real relationship with the customer. Both are in the Slack channel. Both know what's happening on the account. The difference is _focus_, not ownership.
+
+The customer should never have to figure out who to contact. They reach out to either person, and PostHog sorts it out internally.
+
+## What each role focuses on
+
+### CSM
+
+- Operational health and [health score](/handbook/cs-and-onboarding/health-tracking) monitoring
+- Support escalation and follow-through
+- Credit usage optimization
+- Onboarding, training, getting new users set up
+- Renewal process end-to-end
+- Day-to-day responsiveness
+- Health of the technical implementation
+- Surface cross-sell signals from product usage and conversations to TAM
+
+### TAM
+
+- Cross-sell strategy and execution
+- Credit discount negotiation and deal structuring for new credit purchases, invoicing
+- Use case discovery, mapping products to problems
+- Multi-threading into new teams and stakeholders
+- Account planning (quarterly in Vitally)
+- Stakeholder management
+
+### Both
+
+- General customer questions (whoever sees it first)
+- Implementation reviews
+- Retention. TAMs are not off the hook here. Understanding health and usage is a prerequisite for cross-selling, not work that gets delegated.
+
+## What good looks like
+
+- Customer reaches out to either person and gets a fast, informed response. They never think about who to contact.
+- Both go deeper on their focus area than either could alone
+- Customer knows both people, trusts both, feels like they have a team
+- Neither person is surprised by what the other communicated
+- Both are visible in Slack, not just when they need something
+- Both are aligned on the current state of the customer, risks, opportunities and what their counterpart is working on.
+- TAM and CSM alignment on the account happens in public, not DMs
+
+## What bad looks like
+
+- Customer gets told "that's not my area, let me get [other person]"
+- Customer only hears from the TAM when PostHog wants to sell something
+- Customer gets asked "how are things going?" by both people in the same week
+- CSM discusses pricing without knowing the TAM had a deal in play
+- TAM sends a cross-sell email without knowing the customer filed 3 support tickets yesterday
+- Neither person responds because each assumed the other would
+- TAM checks out on health because "the CSM handles that now"
+- Customer has to explain the same thing twice

src/navs/index.js

@@ -1245,6 +1245,10 @@ export const handbookSidebar = [
                     {
                         name: 'How we work',
                         url: '/handbook/growth/sales/how-we-work',
+                    },
+                     {
+                        name: "CSM and TAM dual coverage",
+                        url: '/handbook/growth/sales/csm-tam-overlay-coverage',
                     },
                     {
                         name: 'Why buy PostHog',