Thank you Jeff for sharing that article and video. It's always very difficult to explain this not only to clients but also to experts. I had several discussions (maybe I should call them arguments) with the support staff of the hosting company of one of my clients because they say that the 15 plugins installed on that website are too many and they are the cause of the backend's slow down. Actually, with a news website that publishes 4-5 posts per day with videos and photos plus a Woocommerce plugin with hundreds of products it's hard to say for sure that the plugins are responsible of anything. I will bookmark this post and Mika's post too as a future reference! :-)