Hello,
Today I had a bike race. Xert analyzed a near-breakthrough, however, I wasn’t trying to break through during this race, as I was managing my effort at that point.
In the end, Xert lowered my TP (-7W) and HIE (-1.4kJ). Should I accept this new calculation of my fitness signature?
I don’t understand what I should decide in this situation.
Thank you for your help.
You can always flag a Near BT that you don’t like. 
This is especially true when it wasn’t expected which typically indicates you could have achieved a true BT if you had ridden to failure. You’re not going to do that during a race unless your goal is to get dropped. 
Details at: Flagging an Activity – Knowledgebase
Thank you very much for this quick reply, I will therefore click on the flag to ignore this NBT 