PDSA et al.

["Shper V.L." <shper@vei.ru>]

Denizens,

IMHO

1.	As I see this Shewhart came to his cycle
(Specification-Production-Control) 
not from the viewpoint of scientific management but from the theory of
variability 
(see p.44 in SMVQC). It's variability of process forces us to return 
at the beginning of our process and compare process variability with
tolerances and so on.

2.	As D. Kerridge wrote in his letter on 26.09.2000 cycle PDSA is
broader than scientific method 
'cause scientific method applies to verification of some theory and
cycle PDSA works even when no theory exists.

3.	Taylor created deterministic management where outer forces
(including management) determined all results, i.e. (in my opinion) he
had no profound knowledge neither variability nor psychology (in terms
of WED). And surely this was not his fault. He was an engineer of genius
and a father of scientific management. And being great engineer he
understood scientific method and system problems and applied them.  

4.	Shewhart was the first who understood 
-          that production process is subjected to variability;
-          what follows from this simple fact;
-          how to make decisions under such circumstances. 

5.	Deming understood that variability covers all people do and
applied this notion to all types of processes including management. And
on this way he created the theory of profound knowledge:

Regards,

Vladimir Shper