Managing Rational Team Concert work item changes with process sharing allows the ability to centrally manage any work items configuration changes as described in the below article using the Provider / Consumer concept.  

https://jazz.net/library/article/1077

Moreover any configuration changes at the consumer Project Area that are deemed necessary to be made like adding custom attributes are possible with the following options.

A.      You may customize the consumer's process configuration for any process element. But when you customize the process configuration for a process element on the consumer then the consumer uses its own process configuration for that entire process element. This happens for each process element in an all or nothing manner. Once you have customized a process element on the consumer it no longer uses any settings for that process element from the provider

More on Work Item Configuration and Shared Process in Rational Team Concert can be found in

https://jazz.net/library/article/1005

B.      B. Using fine grained customization of configuration data by defining small configuration deltas to a shared workitem configuration, projects will continue to inherit changes to the shared process instead of completely overriding it. RTC 4.0.4 extended this support by permitting the modification of the name of a custom attribute in a work item. This early support will cover a small set of critical of use-cases and will require manually copying snippets of XML into the process specification, but this is only a first look at the feature. We will continue to grow and evolve it in future releases.

More on fine grained customization of configuration data can be found in

https://jazz.net/wiki/bin/view/Main/ConfigurationDataDeltaUserDoc

My questions/concerns

1.       1. What is the best option to choose between A and B considering that we are adopting process sharing with a potential need to customize consumer PA configurations in the future.

i).       It appears option A is safe as all configurations on the consumer PA are done using the RTC designer; however the inheritance is broken once a process element is customized.

ii).      Also it appears option B is attractive since one is able to customize the consumer and still be able to inherit from the provider; however, the configuration is manual and needs to be carefully performed directly as XML fragments.

2. 22.  How does one avoid making configuration changes (that are deemed necessary) using option A or B directly on the consumer PA in real time but be able to test and promote the changes (from another test consumer PA) all at once on demand seamlessly?

3.       I understand that once we choose one of the above methods (A or B), one cannot change or switch between the two.