The writer of the article you posted apparently does not know about Catholic spirituality or Catholic meditation. His whole first paragraph attributes to Catholcism something which has no place there at all, which is why both Merton and Pennington have been criticized by orthodox Catholics for going too fast into Far Eastern meditation styles.
Had the author read the other writers he mentions on their ideas of prayer, he would have found they would disapprove of his definition of Catholic spirituality just as much as he does.
I suspect that he has read of the other authors and that they would probably like his definition of Catholic spirituality, because he approaches this area from a Biblical POV, that of a firmly independent, fundamental, immersionist, disciplined study of many different other worldviews than merely Catholicism. Part of his interest arises from the fact that he is a successful evangelist planting churches in Nepal, where his opposition is not only Hinduism and Buddhism but also "charismatic christians." Unlike Teresa, he has the guts to tell Hindus and Buddhists and charismatists and Catholicists that their appraoch to spirituality is false and unprofitable.
Searching his Way of Life website on just the word "Merton" yields these papers from the first four of eight pages of related Cloud-written articles:
Thomas Merton: The Catholic Buddhist Mystic
Roman Catholics in Love With Eastern Religions
Evangelicals Turning to Roman Catholic Contemplative Spirituality
The Unifying Power of End-Times Mysticism
Richard Foster, Evangelicalism's Mystical Sparkplug
Contemplative Practices
Contemplative Spirituality: Dancing With Demons
Delusions of Madame Guyon
Beware of Leonard Sweet: Master of Doublespeak
A Visit to the Vineyard Church, Anaheim, CA
Henri Nouwen
The Path From Independent Baptist to the Shack, Rome and Beyond
Brennan Manning
Beware of Brennan Manning
Paul Chappell's Pragmatism and Dangerous Associations
John Piper's Contradictory Position on Contemplative Prayer
Beware of the Ragamuffin Gospel
Basil Pennington and Thomas Keating
Eric Wyse and Contemporary Praise Music
Bede Griffiths, Rome's Expanding Tent
UN and the New Age
Philip Yancey and Dangers in Christian Bookstores
Perhaps you could get a better grasp of his approach by reading a few of these incisive critiques.
I'm sure one's outlook on spirituality is highly dependent on one's hermeneutic.