I'm doing a PhD with a professor with serious funding problems. He invited me to prepare a presentation for a conference, making it clear that he wouldn't pay for my travel expenses. I, in turn, replied that I didn't have the money to travel to that conference. He offered that another student go present my research because that student, unlike me, is ready to pay for the travel expenses.
My professor claims it to be common practice, but I'm having a hard time wrapping my head around the fact that a student who didn't contribute the slightest bit to my research will be presenting my results. Is it really common practice? What do you think about that offer?