Who is we? And what are the two definitions of "over time"?
Productivity improvement today can occur so fast "over time" means week to week.
Did you see how fast GM had to shut down operations? There's a reason their vehicles weren't selling and it went way beyond availability of credit ~ and to the very heart of the question of what productivity improvement has to do with the way our economy works. Ya' really gotta' produce something more than chick cars and SUVs to stay in business.