This final meditation problem is one that only very advanced meditators will encounter, when they’ve reached the eighth of the nine levels of meditation. At this level, there is no more subtle dullness or subtle agitation.
The meditator will hinder their progress if they apply antidotes to problems that they’re not having.
Relax the vigilance you’ve practiced so well to get to this level. Instead of keeping a watch on the quality of your meditation, cultivate equanimity, as described in the Compendium of Higher Learning:
What is equanimity? It is an evenness of mind, a composure of mind, and an effortless steadiness of mind that is achieved through cultivating absence of desire, hatred, and ignorance, along with effort. It keeps the mind from becoming agitated and serves the function of helping not to give the mental afflictions the opportunity to arise.
We have noticed that advanced meditators who apply antidotes unnecessarily tend to be overly worried and perfectionist in their quest to attain shamatha. There’s a letting go to the “me” trying to reach a goal that needs to happen at this stage.