It is, in fact, fairly normal to get a very low number of tests that actually move the needle. Most ideas you have suck and will not improve our conversion rate! This fact will not change if you stop measuring.

The article is right that some ideas aren't worth testing. For example if your checkout page is broken, just fix it.

One mistaken idea a lot of people have is that half your A/B tests will win and you'll get instant magic results. This myth comes from multiple places. Vendors and CRO agencies push case studies about wins, not about the process (which includes lots of losses). Until last year all A/B testing tools (including the one I work for) were nothing but false positive engines [1] due to support for multiple goals without applying Bonferroni, using non-sequential tests, and similar issues. Even if you just ran a bunch of A/A tests you'd get lots of wins!

[1] This is still true to some extent. The situation is now better - VWO, Optimizely and A/B Tasty all have fairly solid stats. There are a lot more than these 3 vendors, however.

(Disclaimer: I work for an A/B testing vendor.)