The whole 6 months no wash thing is just a rule of thumb if you want to get a high contrast fade.
If you think you jeans are dirty, wash or soak them.
I wash/soak my jeans every 2-3 months.
You don't have to avoid water like the plague in your dry denim.
I haven't worn nudies, so I can't comment on the indigo loss, but with my samurais and sugar canes, the indigo loss has been very minimal.
Basically, there is no formula to wearing your jeans. Just have fun with the project.