Core Web Vitals are easy to talk about and harder to move. Server-side tagging helps, but the size of the help depends on how heavy your client-side stack was to begin with.

The short version: a clear-eyed view of what server-side tagging did and did not move is mostly a matter of doing the obvious thing carefully. Run a controlled comparison: same pages, same audience, before and after. Use field data, not lab data, for the comparison that matters.

You may discover your bottleneck was never the tags. That is useful information. That trade-off is the one most teams underweight when they plan the work, and it is the one that quietly determines whether the project ships on time.

If you want a longer treatment, we have a deeper post in the series. For now, the takeaway is small enough to fit on a sticky note: Treat the CWV impact as a happy side effect rather than the headline reason.