Define Thanks For Clarifying Meaning

Thanks For Clarifying
Response from office worker after manager has explained a simple procedure for the 8th time, the last time using graphic displays out of desperation because said worker must be mentally incapacitated to have not understood what was required on the first try.

(upon 8th explanation of simple procedure)
Anita (employee): Thanks for clarifying
Michelle (boss) : Oy. The dreaded "thank you for clarifying," defined as explaining something for the 100th time when you should have understood it the first time. How do you even get yourself dressed in the morning? (and then out loud I said: You're welcome. )
By Kitti