It seems that even Hierotheos would say that his teaching on the centrality and importance of hesychasm is outside mainstream Orthodox thought, but he believes the mainstream view has deviated from the Orthodox tradition.
From what I gather his view that hesychasm should be common among even the laity cuts against the grain of many of the Orthodox voices I have encountered even on Christian Forums. Many seem to think that it should be reserved for monks or at least those who are far advanced in the spiritual life.
Truly if we look to many of the Saints through the ages it would seem that Metropolitan Hierotheos' thinking on the laity practicing "
some" form of hesychasm is actually correct if what you're saying is his viewpoint on it. I'll admit that I'm not familiar with his view on it personally.
Now that's not to say that we who are living in the world are called to the life of an eremetic monk/nun living in a cave, or desert somewhere in an austere location similar to St. Anthony the Great, or St. John Climacus, etc. There is different medicine for different people based on the spiritual sickness. What was spiritually appropriate for St. Anthony the Great, or St. John Climacus wouldn't be appropriate for someone like me who is living in the world.
The basis for what he's referring to is found in 1 Thess 5:16-18, and we practice this by praying the Jesus Prayer, or other prayers.
Really this is an integral part of the concept of theosis that the Orthodox Church espouses which is supported by St. Gregory Palamas, St. Symeon the New Theologian, and others going back further such as St. Athanasius the Great, St Maximus the Confessor, etc.
Overall my understanding is that we as Christians are called to live a life of asceticism on varying levels. So for those of us living in the world we fast on Wednesdays, Fridays, and through the fasts throughout the year, but a monk, or nun would fast the entire year round. Monks, and nuns are also called to a life of chastity, but we in the world are not while being allowed to partake of the Holy Mystery of Marriage. There are varying levels of asceticism, and hesychasm which are appropriate for different people. We're able to practice it as laity, but are explicitly warned to do so under the care of a Spiritual Father, and also with the understanding that we aren't all going to experience the uncreated light as St. Symeon the New Theologian, and others have experienced.
Orthodox Saints, and Elders encourage us as laity to practice the Jesus Prayer just not to the extent, or in the same manner as some of the Spiritual giants.
Last I'll mention that I'm no professor, and so if I'm mistaken on anything here I'd welcome feedback, and/or criticism from another Orthodox poster.
Oh, and my apologies for the OT post.