I feel I am struggling to keep things focused and sharp with the 40D and long lens. It's seems to jump like it never did before in and out. I tried a couple times to track and well, let's just say I need some practice.
What I meant is "I" am struggling. I always had a tendency to shake but with the focus being so precise it's seems harder because of Me jumping in an out. I do want to practice more but the weather really sucks right now. I thank your for getting back to me on this.
After using the 40D all day with the 300 and the 300 +1.4 on it I am very impressed with the focus ability
even when I was "stick picking" to try and achieve focus it worked very well for the most part.
I am not experiencing anything similar to what you are describing here.
maybe try some experiments on static objects to evaluate if there is a problem?
I can;t comment on long glass with the 40D I have not used it enough yet to notice anything different - I am taking a trip tomorrow to photograph bears so I'll be giving it a workout then and get back to you.
This is a very nice image btw. I like it cropped just the way it is.