NPK Wizard And nutrients

[Migrower]

Saw one of the YouTube channels I’ve been watching lately is called Wizard NPK and I believe that the two people working are pretty knowledgeable about the plant itself. But as I’ve been watching i’ve noticed that as they put their Plants into flower the weed structure on their plants seems to curl and claw very bad. They just don’t look like the happy praying leaves I’m used to seeing in a healthy plant,yet they seem to produce quality product. Does anyone have any info on why this is. Is it just heavy feeding?