How many big girls do you know during that era was stealing the show. Show business is more about overall look and not about about performance. I mean, take the group Wilson Phillips. The big girl of the group was the one with the most talent. She was the one that was singing her heart out, probably because she had more heart than the other two combined.
Look at the black community. Big girls in the black community can usually sing the best. They probably have to because lets face it, big people get the shaft most times. They don't fit into what most society believe is beautiful. Remember the group C & C Music Factory, that little skinny black girl was supposed to be singing? She was lip-syncing the song. It was Martha Wash, one half of the group The Weather Girls that was singing the song for that girl.
I guess the lesson for the day is that the people that always are going to judge if you fit into what they feel is beauty, inside and out. Whether you are big, tall, short, a little goofy, gay or just see things differently, always remember, there are more of us than there is of the beautiful people. The people who are different, always sing the best.