That's true for paper, with film, dark green, 12 free way, very short, seconds. In old books you can find information on how to develop my inspection. While in college in the 60s I knew what were then old pros who developed by inspection, 8X10 and 5X7, with MF and 35mm don't think it works as well. I have a couple of packets of Ansco Pinakrotol Green for desensitizer when developing by inspection. Mix one pint 50% water 50% alcohol, mix stock with 1:10 water, soak film for 2 minutes, immerse film in developer, increase development time by 50% half way through using yellow green safe light 10 watt bulb, no closer than 3 feet to the safe life, view for 10 seconds very minute, judging negative density, more of an art than a science. If I can find a green filter than fits one of my safelights might give it a try with 4X5 in D76. No idea where I got the packets or how long I've had them, sealed in foil, don't know if they are any good after maybe 70 years.