By modify, I meant move them in the pose.
If I have a project set up with models, actions and chors, sometimes I will delete the actions from the project so they don't interfere with editing the pose. If you just save the model file only (not the prj), you can close the project and reopen it (or revert it) and the actions that were deleted will be back in the project. But, if everything is embedded in the project, this won't work.
The best way is to just open the model, you are setting up the poses for, in a new project that has nothing in it but the model.
Test projects I'll embed everything, large projects I'll save everything separately, in versions when needed.