The Roman Catholic church would experience unprecedented growth if it could just bring former Roman Catholics back to its fold.
You're right - it is propaganda.
The American Catholic church is experiencing unprecedented shrinkage - a net loss of 10 million+ members in the last year. While it's fair to say that Mainline Protestants are declining faster in terms of percentage, the Catholic Church has lost more in terms of overall numbers...
2008 Pew Study = 54m Catholics
2007 USCCB count = 64m Catholics