If cotyledon still present, never nute when using soil?

TLDR; read last paragraph

Hey guys, so I've learned so much about plants in general thanks to you guys. I'm currently on my first grow using FF ocean forest soil. Seedlings are doing great (I think, peep my journal if you can). At 5 days they are all working on their second set of true leaves.

Ok so onto my question. If the primary purpose of the cotyledons is to provide the seedlings with a starter batch of nutrients, would it be safe to assume until they drop, the plant not only has everything it needs but couldn't take on more nutrients even if present?

Here is a quote pulled from wikipedia:

"The cotyledons contain (or in the case of gymnosperms and monocotyledons, have access to) the stored food reserves of the seed. As these reserves are used up, the cotyledons may turn green and begin photosynthesis, or may wither as the first true leaves take over food production for the seedling.[3]"

I ask because in all of my research I see the common thread of loving plants to death. I've developed a healthy fear of nutrient burn so I'm trying to determine a somewhat failsafe way to determine when a plant could actually start processing external nutrients without having to wait till the poor thing shows signs of deficiencies. The take-away being when the cotyledon shrivels, start applying at quarter dose and move up.

Thoughts? Thanks!!!

you're correct - seedlings don't need much in soil during veg, especially while they are young enough to still retain their cotyledons. a healthy fear of nutrient burn is a good thing. up-pot into a larger grow container when the girls in veg start to show that they are hungry and start using some "cooked" soil (look for a simple recipe here and i only used a gallon of it with "regular" dirt in 3- or 5-gallon containers) for flower. good luck with your grows!

@UnderCoverAgentOrange thanks for the feedback man!

Yup. If your cotyledon hasn't faded and she's growing on then you're all good. She's accessed the soil nutrients quite smoothly imo...