The book generally portrays Don Ippolito as hapless, so I think that description is generally in line with that. The very first time we meet him, he's bringing the American consul a prototype for a cannon... except he has no practical experience with gunnery, and has therefore accidentally designed a cannon that is liable to blow up and destroy its own gunners.

The more that I think about it, the more I think Don Ippolito's actual talent is making cunning miniatures, rather than inventing. He should have considered opening a mail order collectibles business and used the proceeds to emigrate once he'd established a clientele. (But this never occurs to anyone, least of all Don Ippolito himself, who would probably be crushed by this description of his inventing endeavors.)