I think subs are still beneficial (to a stent) without action. Although taking action is always positive in the long term, short term it may be trickier.
In the short term, every action may result in positive reinforcement (when things turn out well) or negative reinforcement / reconciliation (when things don’t go as expected and are in conflict with the messages the sub is feeding you).
Because of this, I think the subs will still work when you don’t take action. Even though it would all be in your head, it will always be a positive message and that will make you mentally stronger and better prepared to tackle the real world once you decide to take action.
I’ve shared this example before and I think it applies here as well. There was a study on the effectiveness of visualization for improving free throws in basketball. They divided the test subjects into three groups: one that practiced free throws, another that just used visualization, and the control one doing nothing.
The group that only used visualization improved almost as much as the group who practiced throws every day for an hour. Visualization is not the same as using subs, of course, but I would assume the same applies.
Having said that, without action subs can only take you so far. The main thing I’d worry about is that, without action, you won’t have the right channels for manifesting results in place (e.g., how are you going to climb the corporate ladder if you don’t have a job).