You write, "You are asking us to believe in a BULLETIN? "
Certain points contained within, yes.
We know with certainty what happened during the retreat: single bridge, no temp bridges, bridge is mined.
In this bulletin -and nothing can possibly be in the bulletin that N. doesn't approve of- there is confirmation that the retreat was planned by N. as described above. (N.) is clear that the only problem with his brilliant retreat plan was the premature detonation by the incompetent Genie officer. We know this because the bulletin clearly describes a "victorious" French Army leaving Leipzig. . . up until the disaster. And, if the retreat had worked according to plan with everyone getting across the bridge... the bridge is blown at the last second.. with only Allied soldiers on it... an intact GA escapes Leipzig ...how could that be anything but another example of N.'s genius? At least according to N.
Thier makes it clear that N. put serious thought into the retreat. Most likely there were no temp bridges because they were not a priority. N. decided that mining the bridge was the priority. It's entirely possible that N. was forced into making the decision between one or the other of these two engineering jobs. That the same officer who went to headquarters asking about building temp bridges was the same officer then assigned for mining the bridge strongly suggests that the engineering resources available were limited.
Bottom line: All of this gets Berthier off the hook. If N. had ordered the temp bridges to be built, there is no reason to think that they wouldn't have. We also know that the story about Berthier ignoring N.'s order has been a myth floated by zealous N. writers as far back as 1879.
Note: I do love reading the bulletins of the GA. Recently while reading a book on the 1812 campaign, I also carefully read every GA bulletin along the way.