I like this idea! I'm building something similar at www.sivv.io. This is a community for knowledge sharing where users share / discover summaries of useful knowledge, ideas or advice that are structured into sections (e.g. background, key point, examples) that can be hidden or revealed depending on the preferences of the reader. The idea is that this forces authors to remove any 'padding' and allows readers to consume the key points as quickly as possible, in theory learning more while reading less. We are currently focusing on the topics of business, behavioural science, personal development, professional development, science & technology and wellbeing. You can sign-up to the beta version at www.sivv.io - any feedback would be much appreciated!