Hi,
I hope Bruce won't mind me 'hijacking' the thread, but the Air War Publications team has put together a blog post dealing with one aspect of ULTRA: the accuracy of the translations. The post can be found here:
https://airwarpublications.com/the-accuracy-of-ultra/
We hope people find it of interest.
Cheers,
Andrew A.
Air War Publications -
www.airwarpublications.com