To relatives, I look them dead in the eye and laugh in a friendly way saying "I hope you're not counting time by talking to me because it sure doesn't count!"
I've only caught 2 so far, and they ended up not doing it because my mentioning it alone brought forth fear and guilt. Then I felt kinda bad.
To witnesses that troll me on forums that are nothing to do with religion, I post in the thread "Gee I sure hope you aren't counting time". I have told friends to do this too on forums and continue to remind my time counting ex friends and relatives in an effort to:
1) bring up the fact that many relatives count time, as do people that "preach online"
2) Make them realise I am a person, not a stepping stone to them receiving positive re enforcement.
3) Get rid of witnesses on sites/relatives that freak right out if anything is even slightly mentioned in a negative way in relation to witnesses, I am referring to the kind that are there to/call to preach, not share ideas or solve conflict.
If your father feels that you are a lost cause, you could always come back the next time with, "Why do you think I feel the way I do?" you may get the canned "It's Satan" response, but if you take the following measure you may have success.
Before that , you need to make it clear, you are his child, and if he as your father gives you the canned response or a response the society gives him as opposed to a well thought out answer specifically tailored to you, for anything you discuss, he is acting out of reflexive answer and not reasoning or loving consideration for you and your emotional well being.
I have pointed this out to some of my JW family members with moderate success. I even got a "Wow, I never ever thought of it that way, you're right", others have reacted with a scoff and an abrupt end but they came back a bit later with a more open attitude.
I am not a professional or anything so my advice isn't guaranteed but it is something else to try. Many people don't realise they have a canned response for things. I used to have canned responses until I realised it is rare 2 people have the exact cirumstances and feelings. So it is better to measure them as people based on what they are and say, not what we perceive they are, or perceive they are thinking.
I tolerated being yelled at "WHAT DO YOU REALLY BELEIVE?" (they were very very frustrated, so okay) right after I left the church for about a year. I didn't even know....I think I'm starting to know now though, and it isn't their way. I still haven't talked it out with my family. I will probably need several more months before I have the right insight/have digested the thought process to discuss it freely and openly.
That and I need to know the true history behind the WTS to be able to assess it as a religious organization, even with things they have said by their own submission that is current doctrine.... I don't feel right going along with much of that.