A guy I used to play pickup basketball with told me something similar about my woodworking videos years ago and I totally blew him off at the time. He only had like 2k subs but he kept saying my 45 minute build videos were too long and nobody was gonna sit through all the sanding and glue up parts. I finally tested it by cutting a desk build down to 12 minutes and it crushed everything else on my channel. Funny how the advice that actually lands sometimes comes from the guy with the smallest channel who's just watching as a normal viewer. Dave earned that steak and honestly you probably owe him a second one for saving your edit bay sanity. How long did it take you to notice the retention change, was it pretty instant or did it build up over a few videos?

Run your finger along the bottom edge of fascia after rain, soft spots mean trouble.