Hi Amy. My husband was the same as your dad - wanted me to have the band not the bypass. In his case it was because the band is 'safer and less intrusive'. However, after we both spoke to the consultant, and hubby was able to ask his questions, he now realises why I want the bypass and will support me through it. Have you seen the consultant yet? If not, when you do, take your dad with you so he can be reassured about your decision. If you've already seen the consultant, were you given the contact details for support groups in your area? You could go to one of these and take dad with you, so he can see for himself people who have been through the bypass and how they are coping with it. Just remind him that you love him but it's your body and your life and you have to do what's right for you.
BTW: whilst I was waiting to see the consultant yesterday, a lady come in for her appointment. She had opted for a band and it hadn't worked, so now she was back for a bypass. I'm not saying it doesn't work for everyone (the band) but there's a greater chance with it than the bypass. Julie