preconnect to 8 origins made LCP 200ms slower

preconnect to 8 origins made LCP 200ms slower
preconnect opens DNS + TCP + TLS early — but each handshake competes for bandwidth and CPU.
— Dev added <link rel=preconnect> to 8 third-party origins 'to be safe'.
— 8 simultaneous TLS handshakes saturated the connection during the critical first 600ms.
— LCP image fetch got crowded out: 1.6s -> 1.8s.
— Cut preconnect to the 2 origins on the critical path (font + LCP image CDN): LCP 1.8s -> 1.3s.
Preconnect is a scarce resource. Browsers warn past ~4 hints for a reason. Spend it only on critical-path origins.
Takeaway: 1.3s LCP — fewer preconnects, faster paint.