I have started several times to collect in one spot the tradeoffs that were made and account for much of the personality of Keykos. Here goes again at this late date in 2015.
External forms of ‘documents’
Keykos things are not generally extractable from platform. Most applications for other systems are welcome however and any external data formats they provide there are also available. See this. Any application whose natural charter is to provide a pure data external form is free to do so.
Upgrading Apps
This is a closely related issue. This page entirely ignores the issue of application upgrades for reasons of either improved behavior or bug fixes. I cover some of those issues here.