Innova or any diet

You don't have to rotate if you don't want to.  I actually wouldn't recommend it if you have a very sensitive dog.  If you really want to switch foods, I would do it once a year (or twice at the most) for a sensitive dog, and make it gradual (just my opinion).

I switch between Innova & Wellness to give her variety.  However, this is not done very often possibly in 2-3 months b/c I only have 1 dog and it takes her that long to get through the smallest bag. 

Actually the Whole Dog Journal does recommend rotating foods.
 
I don't.  They have Innova for breakfast every single day.  I provide variety with the homecooked for dinner.  Since they are eating the meals at different times I don't see an issue with digestion.

I feed Evo on weekdays and Karma on weekends so that my dogs get some grains in their diet. I also add canned food, mainly grain-free formulas that I rotate around.

I started giving raw for dinner (the premade frozen stuff)
 
Bailey gets Innova dry in the AM and raw in the PM.  I dont think Im ever going to rotate kibbles.

I rotate different dry foods mostly on a daily basis,however i understand i'm at the extreme spectrum of rotating. I believe rotating different foods ensures you dont end up with a dog with sensitive digestion.I'm sure if i ate the same food every single day without change and then all of a sudden dove into something different i would have tummy troubles,but because we eat a variety of foods everyday our systems are used to it,i dont see it's any different for dogs.
If owners get their dogs used to different foods from an early age(prerequisite with all my dogs) then upset tums or bowels due to changes of foods shouldnt happen.

Nlkelly i'm not sure if it's too late for your dog,his digestive system may already be fixed,how old is he? All you can do is bring other foods into the fold if you want to rotate,do it very slowly and see if it agree's with him.Personally i just cant bring myself to feed the same food constantly,i just cant see one food having everything every dog needs.Innova and EVO are foods that are in my rotation.

Mine get plain dry kibble in the morning, with "meatballs' of canned food with their sups in them.  All 3 get a fish oil cap, an EsterC cap, and a doggy multi-vitamin.  Buck also gets two MSM/Glcuosamine caps (he is 11 and has a little arthrtis in his hips) and his thyroid pill (he was diagnosed just a little over a year ago with low thyroid).  KayCee, who will be 7 in Aug., had both knees operated on for luxating patellas, gets an SynoviG3 and one MSM/Gluco cap.
 
At night they get a little kibble--always the same, I never change it--and then a meat and veggies.  Meats range from fresh caught & baked fish, to canned mackeral (on rare occasions, pink salmon or sardines), boiled beef liver of heart, boiled chicken livers, hearts or gizzards, occasionall ground beef or chicken breast.  I also have been giving them canned, unsalted green beans and carrot slices, but have decided to rotate the beans with green peas from time to time.  On rare occasions i add baked white or sweet potato, occasionally an egg done in the microwave.  The pumpkin and yogurt I add from time to time doesn't really count and I don't usually mention it.  I do switch meats, but never the kibble.

Sandra- I also wanted to tell you, my sister in law has a very funny/sweet chow/austrailian shep mix, Sasha.  She has tried some holistic type foods and had terrible luck with them.  Sasha can't seem to digest anything other than Purina dog chow.  She tried stepping up to ONE and still- vomiting, diarrhea.
 
Another example of a sensitive dog.  Might not be the super duper food but it is the only thing that works for her.
 
To the OP, you don't have to rotate foods if you dont' want to.  If you find a couple that your dog does well on and you feel like switching it up, go for it.  I usually go 3-4 months before switching kibbles and they are doing really well with that.
 

Shamrock--Do you have any pictures of the chow/austr. shep mix??  She must be gorgeous!

Little update!!  I'm sure you all were waiting in anticipation!!  []  The switch seems to be going VERY well.  My GSD has NEVER had this good of stools!!....of course he is still on half Evo and half the old stuff (Canned Walth Venison and Potato).  They have been consistantly like a normal dog.  I am impressed to say the least.  I am going to start him on some digestive enzymes so if you guyz have any suggestions for 'brands' let me know!! 

Oh, by the way....both my dogs will be 2 in June.