Re: Respect for the Art of Aikido
My thoughts (putting on my flame-retardant suit)...
You can get out of Aikido whatever you want, and no-one should tell you otherwise. If you only want the physical; fine. Only the spiritual; fine. More of one this week, less of the other next year....whatever.
As long as you honestly try and complete the exercises/techniques the Sensei demonstrates to the best of your ability, what you believe and to what degree is your own business. Also, respect for your partners is important, whether they share your views and goals or not.
The only time it might come up is if the sensei thinks/tells you that what you are doing has no place in her/his dojo.