I have read that book. I have also read St John of the Cross, Thomas A Kempis etc....etc...etc. I have a great love of interior prayer.....but..........I would never dream of telling another person how to do it.  You pray as you can...not as you should. Interior prayer is a grace just as the ability to sing in tune.  Many people are far better Catholics in the parish than I am. Many people are far too busy working, raising children and doing works of charity to read pious books or spend long periods in prayer. I am a bit of an introvert I love all the monastic books .......it doesn't make me better.