I think "Merge" is used when you want to sum/concat/mul two Sequential() models. The "merge" is used when you are working with functional API. However, this is not written anywhere in the documentation. Additionally, Sequential documentation has a section called the "Merge" layer, but ...
I know this is a bit late but in your ama in march someone said that you (ninjakiwi devs) are not happy with the state that btdb1 is in and that's why you don't really advertise or try growing it. What are the reasons for that and if you can say what you are changing in bt...