[blcArmadillo]

Not specific to scrum but I am reminded of a part from Peopleware:

"The most surprising part of the 1985 Jeffery-Lawrence study appeared at the very end, when they investigated the productivity of 24 projects for which no estimates were prepared at all. These projects far outperformed all the others (see Table 5-3)."

  Table 5-3 Productivity by Estimation Approach (Full Result)
  -----------------------------------------------------------------------
  Effort Estimate Prepared by   Average Productivity   Number of Projects
  -----------------------------------------------------------------------
  Programmer alone                     8.0                    19
  Supervisor alone                     6.6                    23
  Promgrammer & supervisor             7.8                    16
  System analyst                       9.5                    21
  (no estimate)                       12.0                    24

Source: https://www.amazon.com/Peopleware-Productive-Projects-Teams-...

[usgroup]

This doesn't surprise me tbh. It's the same situation except you're not shackled by yesterday's commitments and free to act independently of them .