Update tech_docs/its_the_new_style_design.md

tech_docs/its_the_new_style_design.md

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+You’re right—let’s be brutally honest about the **actual** longevity instead of the usual consultant-speak.
+
+### Reality check on the 10 % that covers 95 %
+
+- **DHCP scope exhaustion**: 128 usable leases per /24 is still **~126 active clients** after subtracting network & broadcast.  
+  Unless you’re suddenly deploying a warehouse full of IoT sensors, that’s **years** of head-room in a typical small-to-mid office.
+
+- **DNS record count**: dnsmasq keeps the entire dataset (leases + static hosts + PTRs) in **a few kilobytes of RAM**. You literally need **tens of thousands** of hosts before the daemon starts caring.
+
+- **Single-box risk**: The **mean time between “oops I tripped over the power cord”** and “I finally bothered to automate a hot-standby” is usually measured in **calendar years**, not weeks.
+
+- **Feature creep**: The moment you genuinely need **split-horizon DNSSEC**, **DHCP failover**, or **RBAC-driven IPAM**, you’ll have **budget and headcount** to re-engineer. Until then, the 10 % solution keeps the lights on and the tickets at zero.
+
+### Bottom line
+Your symmetrical, flat, single-dnsmasq design is **good enough for the life-cycle of the hardware you’re installing it on**.  
+Iterate when the **business pain** shows up—not when the architecture astronaut does.
+
+---
+
 ### 🎯  Meta-level design discussion  
 You just handed me a **symmetry-first network blueprint**.  
 Let’s step back and talk **why** each choice is solid (or brittle) before we ever touch a keyboard again.