TOD combo switch plus manual hubs

If I understand this correctly and I spent enough time reading the archives this is what I think is going to happen.

Do the tod combo mod (2wd, 4wd, tod) plus manual hubs I could have the hubs unlocked and the tod switch in 2wd and the front drivetrain shouldn't spin at all. maybe a little because of friction and momentum but not actually being powered and being disconnected at the hubs.

seems like I should get better mpgs and less drivetrain wear.

Is there a downside besides having to get out and lock the hubs? If I want 4wd high I just lock the hubs and flip the switch inside, if I want stock like tod operation I just lock the hubs and select tod.

Seems like a win win for little $.

The MPG "gain" is very minimal. But, just my opinion, you save in the wear and tear department.