Actually, if Tom really is a good public speaker and has the ability to talk on a subject and entertain at the same time, then I don't see why he shouldn't have a chance of being a guest speaker on a ship.
Some people seem to have a natural charm and a way of keeping people interested in what they have to say and if Tom has those qualitities and chooses a subject that he is knowledgable & comfortable with, then why shouldn't he be given a chance to become a guest speaker ?
There are a number of smaller cruise lines that do have guest speakers and many people cruising on those ships love attending various lectures but they get somewhat spoilt if the lecturer is one who drones on and on and is not able to gel with their audience.
If Tom has that special charisma factor and can entertain an audience then I don't see why he can't at least find out more by speaking to the cruise lines who might possibly give him a chance.
...as long as the speaker doesn't repeat themselves, saying the same thing over and over.
Nobody is saying he shouldn't do it. I think the larger issue here was the use of "expert" when "conversant" is probably more appropriate for someone who has merely read up on a topic, for 182.5 hours (or 183 in a leap year).
Well Dave, I just got back from Tahiti on the Paul Gauguin and I attended a number of lectures ranging from Tahitian History to Tahitian Black Pearls. It wouldn't take me more than 180 hours of study on either topic to present a good informative lecture (with pictures, power points etc..). I purchased pearls, visited some historical sites, spoke with the natives. Met the owner of Bloody Mary's and talked about starting a business on the islands, etc...
So, although I have you as a skeptic, I'm very confidant I could do this and do it well.
If I were hiring an expert as a guest lecturer on a ship, I would be looking for someone who is a long time employee in the industry in question. If I'm hiring a bridge teacher, I want to see a resume full of years of teaching and some tournament wins as well, not just "I know how to play bridge."
Studying up on a subject may be entertaining and educational for the person doing the studying, but cruise lines are more discerning in their choices of lecturers, especially since their audience is very discerning. People going to these lectures often are experienced or even experts in the field themselves, and they want to hear someone speak who knows even more than they do.
Don't forget that every entertainer, every lecturer, every port and shopping talk gets rated by the passengers in their comment cards. Someone with a passing knowledge in the subject, and hasn't worked in that field for years, is bound to not be around the cruise lines very long.