I'd argue it's not my job to "shield the team". It's my job to enable the team to question "dumb shit" and put them in a position where they can discuss these matters constructively with management (or whomever).
Also - I "deal" with underperformers because my team needs to deal with them. It all comes back to "what benefits the team".
I see that there are a lot of different varieties of agile coaches out there.
I'd argue it's not my job to "shield the team". It's my job to enable the team to question "dumb shit" and put them in a position where they can discuss these matters constructively with management (or whomever).
Also - I "deal" with underperformers because my team needs to deal with them. It all comes back to "what benefits the team".
I see that there are a lot of different varieties of agile coaches out there.