...the cooking time change? For example, if a recipe called for 4-6 boneless, skinless chicken breasts on for (4-6 hours) and you only made 2 would you need to shorten the cooking time?
In my experience, chicken breasts range from 4 to 8 or more ounces. Some are frozen, and some fresh or thawed. Most crock pots have two or more temperatures. So, the best way to determine whether or not a dish is done is a meat thermometer. If the breasts are 160F they can't transmit salmonella, and if they're 170, they are done.