you might think that, then examine a general doing multiple camp attacks getting 9% of your troops back opens up new possibilities.
If you do a lot of adventures I would seriously get your calculator out and do a rough estimate of what 9% of your bronze sword / platinum sword, brew and breadmen ( if you use them) works out to be over a year.
To the OP consider Fast learner on MG (3/3) and either 2/3 or 3/3 in confident leader (dropping weekly maintenance and master planner), push blocking generals up to Garrison annex.
From a personal perspective I cannot see the point in Navigation crash course in any general other than ls general and taverns. Unless you don't block then it might be worthwhile.