Who am I to criticize my students' English when my Japanese stinks?

  Yesterday, I had to write a letter to a junior high school principal requesting that he permit a teacher at his school to present at a conference with me. I wrote the letter in what I thought was fluent and persuasive Japanese. I asked my wife to take a look at it just to make sure there were no typos. Immediately she took out a red pen and started to correct. When she got to what I thought was the most compelling part of the letter, she asked if I has used a translating program. I, the teacher who curses the invention of translating programs often when he reads his students' written work, was being accused of using what I despise the most. Although she did not mean to insult me, my wife's appraisal of my Japanese felt, for a moment, absolutely devastating. It was like working your whole life to become a Picasso and being told that you can't even finger paint. 

  The past few years, in my teaching methodology courses, I have been very strict in correcting students' English. In my evaluation of their writing, I have designed rubrics that frankly tell them if their English has shortcomings. I thought that even if the criticism was a little tough, it would be good for them. To be hired as English teachers, to be superior English teachers, they must possess a superior level of English. However, being on the receiving end of the tough love has made me reexamine this notion. The semester has just ended but next semester I would like to talk to my students about this.