As I was reading the Perfect Matrimony it states, "The sound of the three powerful vowels must be prolonged like this: IIIIIIIIIII, AAAAAAAAAA, OOOOOOOOOO, that is to say, extending the sound of each vowel. The air is inhaled to fill the lungs, then one exhales it. One inhales counting to twenty, holds the air counting to twenty, and then exhales vocalizing the letter I [editor’s note: the I is pronounced like a long e, as in the word bee]. When exhaling one also counts to twenty. Repeat the same procedure for the letter A and then continue with the letter O."

The part that confuses me is the counting to 20 while inhaling, holding the air while counting to 20 and exhaling counting to 20. How is it possible to exhale while vocalizing the the letters and count to 20 at the same time? The other books and articles I've read on this site about mantras don't say anything about counting while vocalizing the mantra. So saying the Mantras without counting to 20 is useless? This is so confusing...