Not so much saying them, of course. The New York Jets' loquacious rookie coach has no trouble speaking his mind. Reading and writing, though, have made Ryan cringe since grade school.
That's the effect dyslexia can have, even on the most confident of NFL coaches.
"It was really frustrating," Ryan told The Associated Press. "So much of school, you have to write, but I just struggled. I couldn't help it."
Dyslexia is a language-based learning disability which affects people's abilities to read, spell, write and pronounce words. According to The International Dyslexia Association, perhaps as much as 15-20 percent of the population has symptoms of dyslexia.
"They gave me a test, too, and there were like 100 words, not real words, but letters just thrown out there," Ryan said. "It might've taken me, I don't know, maybe 15 minutes to read it out. They brought in my youngest son, who was maybe 10 or 12 at that time, and he read it in like a minute.
"The further we went along with it, the more I realized, 'Man, oh, man. I can see where I definitely had it."'
It's a stunning admission by a man who has exuded so much confidence and bravado since becoming the Jets coach in January.
"It's probably pretty common for someone who has communication problems or issues to be very reserved, shy or laid back," said Jets safety Jim Leonhard(notes), who played on Ryan's defense in Baltimore last season but only recently heard about the coach's dyslexia. "Rex is the total opposite. He's too competitive of a guy to let something like that slow him down."
That wasn't always the case. Ryan remembers the anxious moments when he was called upon to read in class and the page appeared nothing more than a muddled mess of letters. And there were all the miserable scores on spelling exams.
"It wasn't like they had spell check back in those days, so it was impossible," he said. "I was a terrible student."
It got so bad Ryan would often skip school unless floor hockey or softball games were planned.
"I never wanted to embarrass myself," he said.
Adding to Ryan's frustrations were the facts that his mother, Doris, has a doctorate in education and was a vice president of the University of New Brunswick in Canada, and his father, Buddy, was a two-time academic All-American before becoming one of the NFL's greatest defensive minds. Ryan's older brother, Jim, has an MBA and a law degree.
Even Ryan's twin brother, Rob, who is Cleveland's defensive coordinator, "was pretty decent, too," he said, laughing.
"I was like, 'What the heck's wrong with me?"'
Well, nothing when it comes to coaching. Ryan, whose Ravens defenses were among the league's best the last several years, believes his dyslexia might have even helped shape his approach.
"He's a fighter and a competitor," Leonhard said, "and you can tell he probably got some of that from having dyslexia and overcoming it."
Many coaches today use colors to code their playbooks and game plans, but it's something Ryan has been doing for as long as he can remember to make things easier to comprehend.
"We can go back as many years as you want to go and you'll see it that way," Ryan said.
One set of plays might be green, while another yellow, and so on-a colorful learning tool that amused Jets defensive coordinator Mike Pettine, a former assistant under Ryan in Baltimore.
"It would drive him crazy," Ryan said. "He would say, 'Don't say that stands out! How can you read that better?' This was before I even knew I was dyslexic."
The Jets also help Ryan with TV and radio commercial spots by reading the copy to him and letting him repeat it before taping.
"If you talk to me, I can pick things up better than I can just off a white piece of paper and black letters," he said.
Still, being dyslexic isn't something normally associated with NFL head coaches. Ryan was open about it when he interviewed for the Jets job, as well as previous opportunities.
"I never wanted to paint a false picture of myself," he said, "because if I got that job, I wanted to be myself."
Despite the struggles, Ryan was able to earn a master's degree in physical education from Eastern Kentucky. And then there's all he has achieved in the NFL.
"For the weaknesses I have with spelling and all those other things with being dyslexic, I have a lot of other strengths also," Ryan said. "I want people to know that you can have dyslexia and still reach your goals."