I just met with a prof I hadn't seen in 4 years. When I asked if he wanted a copy of my official transcript, he said, "Well, you've done well in my classes and that's most important to me...but if you're comfortable with it, that would be fine."
I told him that my transcript was pretty bad but indicated that there was a definite upward trend (as in, going from a 1.83 GPA to 3.60) and explained my circumstances. He was pretty surprised about that and said he would be sure to include that in his LOR.
Just one more reason why you should ask for LORs in person if possible....