Of course. And this relies on your CI system having 100% unit and system test coverage, including testing external API's, CSS bugs, browser compatibility, etc. Are you certain that your system does that? More importantly, are you certain that investing the time into testing that your checkout button is not covered up by some random element due to a missing ";" character in your CSS file or a missing 0 in the width percentage value will eventually pay off? It should be scary to push to master if you hold master to be deployable at all times. Unit/system testing or not, you will never have guaranteed test coverage, and even if you try to get to it, you will spend infinitely more time doing that, than doing a reasonable amount of unit/system automated testing + good human QA.