As some of you know, I teach workshops and coach executives and managers on presentation skills. I've found politicians to be fascinating studies in the ups and downs of public speaking. Many of the best would lose points in a public speaking contest but they remain highly effective due to their overall performance. [It is possible to be too smooth.]
The most eloquent American presidents in my lifetime were - no surprise here - Kennedy and Reagan. Their pacing and use of phrases are extraordinary and they were able to carry that magic onto the stump. Bill Clinton was eloquent but not memorable. Jimmy Carter fell into an odd staccato. [His speeches are a real contrast to JFK's fairly rapid pace.] Lyndon Johnson, by all accounts a dynamic figure in person, had a schoolmarmish persona when speaking formally. Reagan's voice possessed a warmth that was assuring whereas George H. W. Bush's voice tended to grate. [One observer famously said that Bush reminded every woman of her first husband.]
There is a strange similarity between Barack Obama and George W. Bush. Both can do a grand job of delivering a set speech - see Obama's speech after the Iowa caucus victory and Bush's speech at the National Cathedral after 9/11 - but their stump speeches fall into the "flirting with disaster" category. Due to Bush's notorious misuse of the English language, his impromptu efforts could be, as one wag described it, like watching a fat man on ice. Obama, a well-educated man, drops his "g"s when on the stump and sometimes, when searching for the end of a sentence, seems as lost as his predecessor. Ted Kennedy could give inspiring set speeches but his impromptu utterances could cause you to shout - as a Doonesbury character once did - "A verb, Senator, a verb!"
So far, Mitt Romney's speaking style tends to be more workmanlike than eloquent. I've heard one of his speeches that would fall in the eloquent category. The rest pretty much resemble cabinet-making. That may not be bad. Eisenhower and Truman were carpenters when it came to oratory and their presidencies show that we may place too much emphasis on eloquence.
Eloquence without substance is entertaining but little more. A beautiful performance by a modern-day empty suit (think John Edwards) is like the extravagant military uniforms worn in nations where the main job of the armed forces is protecting a dictator or plotting a coup. The uniform and all of the decorations look nice, but what do they really represent?