I used Dektol for sheet film many years ago--for films like Super Panchro Pan X in 4x5 exposed with flash. Dektol was a favorite for press photography where high contrast was important and grain was not. These older films responded well to Dektol diluted 1:2, although DK-50 was usually better and preferable giving slightly lower gamma. In response to your question, Dektol/D-72 was used quite a lot for film years ago (late 50s and early 60s). As film speeds increased and press quality improved from newspaper to magazine reproduction, D-76 pretty much replaced Dektol for film.