I come from the Software Development industry, and in the last several year I work closely with developers, architects, product people and management. If you work with people from different departments and levels, you usually have to adjust what you are saying. For example for top management, you only need to describe the big picture, the important tradeoffs and the value proposal, and product-oriented members are usually not that interested in the tech details. However, a developer needs the implementation details and core logic behind it, and not necessary the whole architecture. If you want to destroy these barriers, you have to have a multi-level description that can be touched anytime. Also, if you work in a multi-cultural environment, you often would find that minor differences in sentences could have huge impacts - and the best common language you could use is drawing. This is where I was first touched by this idea, if you could draw on multiple layers, you could present this drawing to different departments and levels, hiding those details that are not interesting for the given audience, but also letting them know that it is either part of a bigger picture, or that this is not all the details you have. This should increase teamwork and getting involved, everyone could understand better where are they in the picture. Also, I know several people who are trying to do TDD/BDD, and if I sit down with them describing the details, it always ends up with compromises, and not real TDD.
It looks like to me, these concepts works well as an idea, but they are hard to implement. The flaw I usually find is these processes are too rigid, they are either burning efforts since the tests and acceptance criteria should be defined by multiple people (product, dev, and QA), or they are not detailed enough. But if you say that the product expectations could be clearly defined (by the PO/PM), which could be derived to exact tests/behaviours/expectation by the QA, and the HOW is being done by the dev, it would be more agile, more organic. Nonetheless if you could really wire in these concepts or flows to not just real code, but real products, and monitor their behaviour there, you could analyise the bottlenecks, investigate given scenarios or just simply collect data to your next steps, that would be awesome. My expectation was to create a great product that would help me describe the product we are creating in any stage, for any member I need to collaborate with. My current expectation is much more - I want Expectide to exceed that and help everyone who has a complex process define, analyse and optimise it.