What if customer experience was the only metric that mattered? We find that our clients who focus on this as the main metric see sales double... which is really what all the suits care about.

Just imagine how much better Google would be if user experience was 100% of their focus, not shared with advertisers (Google's real customers the way it works today).

True. It is a wonder that they've been able to keep the home page of google.com just focused on search.

That is still the best example of usability and user experience on the internet, IMO.

But how can you show how proactive you have been in your quarterly performance review without testing out various user funnel strategies, optimizing conversion rates and paying consultants for A/B tests?

You mention tactics. Instead, focus on metrics trends. Optimizing the customer experience may include the tactics you've mentioned, but if you walk into a review and show that your customers are happier (net promoter score, or clips from user testing, for example), conversion rates are up, and online revenues are up... that would be pretty darn good evidence of a job well done.

In reality, the reviewer is thinking, so what have you done for me lately?