Until there is a more systematic review I think it is wise to time self impose time/mile limits for steer tires. Maybe 15,000 miles and 3 years for the steers. Just rotate them back to the drive position for a few more years and put new tires on the steer wheels. Rettroband or not, driving the steers to failure is probably not the right solution.
I have been thinking of this idea and had the following scenario of replacing the steer tires every 2 years and rotating them to the back. By doing this, your front tires would never be more than 2 years old and you back tires would never be older than 6 or 8 (depending on whether you have a tag or not.)
By year:
Year 0 (all new tires)
Steer 0 Years old
Inner Dually 0
Outer Dually 0
Tag 0
Year 2 (no rotation, just replace front)
Steer 0 Years old
Inner Dually 2
Outer Dually 2
Tag 2
Year 4 (rotate steers to inner dually)
Steer 0 Years old
Inner Dually 2
Outer Dually 4
Tag 4
Year 6 (rotate steers to outer dually)
Steer 0 Years old
Inner Dually 4
Outer Dually 2
Tag 6
Year 8 (rotate steers to tag)
Steer 0 Years old
Inner Dually 6
Outer Dually 4
Tag 2
Year 10 (starts over - rotate steers to inner dually)
Steer 0 Years old
Inner Dually 2
Outer Dually 6
Tag 4
Advantages
1) Front steer are never more than 2 years old
2) Does not cost any more than replacing all tires every 8 years
3) Lowers risk to front steers - maybe enough to not get Rettrobands?
Disadvantages
1) Have to go to tire dealer every other year
2) All tires have to be the same size - maybe you can change the smallest tire to the largest so they all match?
3) If you have Rettrobands, you need to go to NIRVC every other year to have them removed and reinstalled for new tires. Not sure what NIRVC would think of moving the bands so often.
4) Slight risk to damage during the remounting of tires?
5) At the end of each cycle, one set of tires would be approaching 8 years old...maybe too old for some folks risk tolerance.
6) All tires would have to be same brand/type so they match when on dually axel.
Note: If you do not have a tag axel, this would be a 6 year rotation.
Just an idea.
Comments welcome