no tcw is not lucas canon most of the retcons is from filoni alone even if you say the eu was never canon and it also contraticts the films but grievous fighting grievous many times is not a contratiction and neither anakin fighting dooku i mean maybe anakin fighting dooku the many times that happened is a contratiction but it would not be a contratiction if it didn´t happened many times and obi-wan and anakin fighting him at the same time is a contratiction to and when grievous said i have been trained in your jedi arts by count dooku he meant that dooku never train him in the jedi arts only taugh him how to swing a lightsaber like ventress told grievous it doesn´t mean that they never meet before