Tool Set for Improving Transactional Processes

I happen to agree with you with one exception.  Regression can be very helpful in the services environment.  When you analyzing possible associations between multiple explanatory variables (independent) and one response (dependant) variable, you may desire to determine the strength of impact for each of those variables on the response variable.  This is when regression can be very helpful. 

What may also be of interest to you is if you are in a call center environment and a supervisor desires to understand the handling times of his/her team with respect to the center average.  He/She can get a good sample size for her team and use statistical inference to determine how her team is performing.  Hence, hypothesis testing can be valuable. 

Otherewise, your statement is very true.  We have eliminated DOE, taguchi experiements, and response surface methods from our training and installed benchmarking for continuous improvement and process simulations tools for operations planning.

Hope this helps.....