Yes. We get called on to set-up the instruments without these controls at times. In these circumstances it is our policy to inform the investigator that we are no longer doing science, we are setting the instrument so the data looks a certain way based on our expectations and experience. Results from these experiments are invalid and need to be repeated with the proper controls, any conclusions drawn under these circumtances are highly suspect at best. If you are going to spend the time and considerable money required for flow cytometry experiments please take these steps to make your data meaningful.