A huge, absolutely huge, part of the margin problem is plant loading. With the shrinking volume (not dollars, but square feet of product) in most plants the fixed overhead has crushed margins down.
(Fixed here being depreciation, basic management, utilities, facility maintenance, etc.) Tireman sounds like an arrogant 13 year old know-it-all when he says "depreciation is the only fixed expense".
Tireman and his foolish consultants think you can cut your way to prosperity. The opposite needs to happen for 3M to actually return to the lovely 22% margins of the past. 3M needs to hire sales teams, not marketers, to go out and sell the existing factories out. Even just 1,000 dedicated sales reps globally would make a Wall-Street-noticeable difference in 3M's fortunes almost immediately.
3M is near stalling due to low volume in many large manufacturing portfolios. If 3M had the courage and brains to try and fill the plants, most of those plants would succeed. Unfortunately 3M executives have developed an allergy to money that prevents them from doing anything to make any.