Whats the handle material? Tru-Oil has some problems handling VERY hot water. Over several times of being exposed to very hot water, Tru-Oil will gradually start dulling, then turn slightly "milky"
I have a couple of Fossil Damascus kitchen knives (that I made) in the house with wood handles/Tru-Oil finish. Both have 12 coats. One is African Blackwood, and the other is Striped Ebony. Keeping in mind that at NO TIME have/will these knives be thrown into a sink of water, or placed in the dishwasher...... after use they are immediately cleaned with warm soapy water, then hand dried. (I don't have to worry about the blades, as they were finished out with clear Gun-Kote).
The African Blackwood handle looks like the day it was made. The Striped Ebony is a different story..... the finish has turned slightly dull/milky looking, with an odd texture/feel. Although I've not done a lot of experimenting, that situation tells me that various woods and/or non-synthetics have much to do with how the finish holds up on any given one.
Personally, if I build culinary cutlery for anyone, I ether use synthetics, or stabilized materials. There's a reason that the paperwork I send with a knife has this statement: "NEVER, NEVER, put your knife in the dishwasher (don’t laugh, a number of folks have done this and really wrecked their knife.)"