Jebra was talking about typical alchemists in this world who created a series of common practices and unspoken rules.
What he didn't know was that Angor never studied alchemy in the "common way". While Angor might know about certain conventions among alchemists, he didn't have a reason to copy their examples. Till now, he mostly did alchemy works while following his own pace.
He did leave alchemy reports after creating items. But in his papers, he usually left some simple questions and some brief ideas about how to improve his future works, unlike the other alchemists who would record each of their movements when crafting something and keep everything noted down.
Of course, Jebra had no idea of Angor's habits, so he could only surmise Angor's working routine by referring to the other alchemists he knew.