And to add to what I said, this practice of partially baking loaves then finishing the process later arose from wanting to serve freshly-baked bread all day, without having it take an inordinately long time. It was also useful when bread was baked at a large centralized location, but sold at smaller outlets elsewhere. A large number of loaves could be parbaked at the central location, and then smaller quantities finished on location at the outlets.
Having said that, it’s impossible to say whether a twice-baked bread is automatically superior to once-baked. A lot would also depend on the quality of the flour, the nature of the oven, etc.
And to complete the crisscrossing between parallel threads, here’s a link to what I said in the rye bread thread on Our fathers bread being in twice baked:
