I wonder if any of you has seen Stefan Zucker's 1999 documentary "Opera Fanatic" in which he interviewed some of the greatest divas of the 20th Century such as Fedora Barbieri, Leyla Gencer, Anita Cerquetti, Giulietta Simionato, Iris Adami-Corradetti, Carla Gavazzi, Gina Cigna, Gigliola Frazzoni and Marcella Pobbe. They discuss chest voice, style, vocal technique, expression etc. But there are tons of funny moments especially with Barbieri and Gencer.
What's stunning in this movie is the divas' views on chest voice. Some are strongly against it (Barbieri) and claim they never used it. Some deny its existence altogether (Simionato), and some say it's okay to use it if it comes naturally(Pobbe). Gencer and Gavazzi find it preposterous that other divas are against chest voice and even deny they ever used it.
My conclusion from that is, the term "chest voice" is somewhat misleading. Barbieri and Simionato cringed at the word and even demonstrated the difference between what is correct and what is archifaux according to them that is "chest voice".
In case you're interested, a part of the film is on youtube. Here is the first part:
The version I have downloaded is of a much better quality and I have watched it over 5 times in the last couple of years. Every time it makes me laugh and I get something new out of it.