When offered the choice of cutting features to improve the tool, designers preferred the annoyance.)
good for them!
users generally prefer more features to more/better un-released in-house tools.
Some built all the data through tools. There was no hot-loading of data. Designers could make changes, but in order to see them in game they needed to save their stuff, stop the game, build the game, and re-launch the game.
Caveman uses this for some of the stats for animals. newer parts of the animal (monster) type definitions are data driven, older parts are still hard coded.
Some have had built-in systems that allowed live tuning of data.
In this case designers could view and modify the data on the console but needed to write them down and hand-enter the final values.
Caveman has that, but in the form of a generic editor that can be hooked up to up to 10 objects at once with just one line of code each, then used in-game to adjust things.
Later i discovered i could do the same thing with the built-in rigid body modeler/animator.