I havn’t seen Ryan debate.
[After working as a legislative aide for Former Wisconsin Senator Bob Kasten] Ryan became a speechwriter for Empower America (now FreedomWorks), a conservative advocacy group founded by Jack Kemp, Jeane Kirkpatrick, and William Bennett. Ryan later worked as a speechwriter for Kemp, the Republican vice presidential candidate in the 1996 United States presidential election. Kemp became Ryan's mentor, and Ryan cites him as a "huge influence." Ryan then worked for U.S. Senator Sam Brownback of Kansas before returning to Wisconsin in 1997.
Add to that his 14 years in Congress defending his economic plans, and you have the basis of a good debater. I thought that I had read someplace else that he had debate team experience, either in HS, or at Miami of Ohio, but I can't find it right now.