In Vipassana circuits today it is taught that you should observe, and not control. But keeping the observing mind, mindfulness, is a form of control. It is maintaining a sense of presence. Yes, you are not controlling with force of will, trying to channel thinking in a particular direction, but nonetheless you are controlling. throughout the suttas in fact we find this idea of control, or more usually, restraint.
This takes effort – hence the continual exhortation to ‘exert’, ‘strive’, to be ‘ardent’ with ‘unremitting mindfulness’. How to do that, without controlling?
Here is Ledi Sayadaw, a particularly direct Burmese master of recent times:
In this world, a mad man who has no control over his mind is of no use either in work for his own benefit or for the benefit of others. Even when eating, he is liable to upset his plate and walk away. It is impossible for him to concentrate on work for the benefit of others. When this mad person is properly treated he becomes sane and mentally stable enough to perform work both for his own benefit as well as for the benefit of others, just like normal people.
Similarly, ordinary sane people resemble the mad man who has no control over his mind when they undertake the subtle work of tranquillity and insight. For example, when paying homage to the Buddha, the minds of normal people do not remain steadfastly and continuously concentrated on the noble and incomparable qualities of the Buddha. Even when repeating the stanza “Itipiso…” their minds wander. If they were obliged to start again from the beginning whenever their attention strayed, their task of repeating the stanza would never be successfully completed. It is only because they have committed the stanza to memory that they are able to repeat it to the end. The same happens in all the exercises for mental training and development. This is how ordinary sane people are just like mad persons when it comes to developing concentration and insight.
Let all take heed! In the case of such persons who have no control over their minds, far from being able to achieve the path (magga) its fruition (phala), and nibbāna, their rebirth in one of the fortunate realms (sugatī) after death is uncertain. In this world, people who have no control over their legs cannot successsfully perform work that must be done with the legs. People who have no control over their hands cannot successfully perform work that must be done with the hands. People who have no control over their speech cannot successfully perform work that must be done with speech. People who have no control over their minds cannot successfully perform work that must be done with the mind. The work of meditation must be performed solely with the mind. Hence it is that worldlings, both laity and Saṅgha, who have no control over their minds cannot successfully practise meditation. Their efforts are mere imitations.
Clicking here you can link to the full text of Ledi Sayadaw in ‘A Manual of Respiration’