Does anyone find these kind of exercises(one armers deadhangs and campusing) has a detrimental affect on their climbing grade, as their energy is going away from climbing on rock.
What would be a good ratio for these exercises against actual climbing ?
2 days climbing/ 2 sessions of exercises per week could be doable for me.
The questions you need to ask yourself are "what are my weaknesses?" and "what do I need to improve on to do the routes/problems that I aspire to?" If you can do 1-4-7 on a campus board, but struggle to climb 7a+ outdoors, then yes, climbing is going to be a better use of your time. If you have climbed outside a lot, and feel you have hit a ceiling on certain problems due to lack of power, you need to work on your power.
Are your weaknesses locking big holds? arm/shoulder strength exercises are the way to go. Do you struggle to generate movement when foot holds are poor? possibly work on your power.
The problem many climbers have is that they want to be improving continuously and climbing well all year round. My advice would be to look at the year ahead and decide when you want to be climbing well, and when you are going to have time to train. This is what ALL other sports people do.
Overall I would say that no, your climbing won't suffer by doing specific strength training. I know I'm a long way off being any good, but I have improved significantly over the past couple of years by working on basic strength. But then I'm made of twigs.