I think you misunderstand me I don't mean to imply that the Postgres developers have decided to be sloppier in their development practices or anything like that. When I say 'less conservative in development' I mean that scope is an aspect of development. When a project's scope increases, so does it's workload and complexity; a development team can either allocate more resources and time to the project or let quality slide. This is a truism and I mean no slight to the Postgres people who, in my experience have consistently delivered a very stable project to date and may very well be able to handle a broader scope with no loss in quality.
