Yes, your devotion will grow at "doubled rates'' as you give more and more service to the Supreme Lord. Krishna states in the Bhagavad-gita that the one who is spreading KC is the one most dear to Him. So, you are doing the most valuable service to the Lord by introducing your class-fellows and friends to this Sankirtana movement, and therefore, you will feel more and more increase in your devotion to the Lord. Please continue to do like this, and Krishna will be pleased, and you will be always happy in this life, and what to speak of the next.
Letter to Terry and associates, 22 March, 1968