Yes can can be mixed with dry food. However I am not a big fan of can food - I did use it in the beginning and only did a tablespoon here and there, but would rather mix in stuff that is not processed and more nutritional and fresh - Like boiled chix, sardines, salmon oil, yogurt, cottage cheese, egg etc.
Is you dog not eating his reg kibble hence why you are using can food?
I had this same question when we first brought Berkley home, we just went with what the manufacturers recommended. We mix in canned food with every meal. When she first came home, she wouldn't touch dry kibble, so we kinda had to mix it to get her to eat. We started her on Nutro, and their canned food is chunky with a "gravy", so it moistened the kibble. However, now we are switching her to Canidae, and their canned food is more solid, no gravy to it at all, but she seems to like it. Canidae recommends 75% kibble, and 25% canned. We occasionally give her some yogurt, or an egg, to switch it up, but she still won't touch straight kibble. We get about 4-5 meals per can, and its only about $1 per can, so it doesn't add much to the cost. In the long run, I hope to get her off of canned food, but i guess thats kinda up to her...lol.
there are better things to give than canned food to switch things around. you can give certain fruits and veggies, plus add yogurt eggs (raw or cooked-raw i would say only once a week). These would all be a healthier choice than canned food