Tricking plant into thinking it’s in a smaller pot.

Don’t know if this will work well, but I’m giving it a try next season. One thing that is a problem for people is transplanting. Personally I haven’t had any problems but I’m only on my second grow. But it’s scary for some. But going from seedling stage to final pot seems unwise. It’s easy to over water and the roots sort of have to much room, ( at this particular time), that’s the problem. So people, I’m getting some thin plastic material, might even use a old nursery pot (the cheap kind),otherwise I’ll cut a strip the same circumference as a 6” pot, lay it in the final pot during preparation. Imagine a sleeve that is split.
Width I think should be about 5”. What you want to do is create a wall so to speak with this sleeve. Fill in the pot like normal with sleeve inserted. Put your baby in, and water it (always being careful to not overwater) I believe in a couple of weeks you can remove the sleeve Just ease it out, and since it is split you should be able to remove it without any harm to your plant.

Or simply press around pot exterior to loosen plug.
There is absolutely nothing to be scared of when transplanting.

Just let em dry a bit.. pop em out pop em in, cover, water in, done..
Nothin to it!

I do something similar w solos. 2 solo cups, inner one has most of the cup cut away from sides and bottom. fit inside another cup w holes in bottom. fill w soil and pop in plant. once it's big enough to transplant pop off the outer cup and drop into larger pot. no more spilling dirt or tipping plant upside down trying to get it to pop out of pot. don't have any made up rn but can show u later if u want.

What do you mean too much room? I don’t follow. Over watering is definitely the biggest problem people have in my opinion, but you just wait until the dirt is dry then water, and it’s hard too explain how wet the dirt should be without being able too show people but they can just stick their fingers in the dirt a few times a day and lift the pot until it just starts dropping a tiny bit then water, and remember what the dirt was like before the plant had any droop, stick your fingers an inch or two into the soil and you want it moist and darker but not wet where you could like roll it into balls. Sometimes I’ll go from 4 inch pots directly into 400 gallon smart pots and have never had a problem, usually I go from 2 gal pots though, and occasionally 5gal. And if I’m just fucking around I’ve just put clone tray plugs directly in the ground and they have always been fine, just have too keep more of an eye on them lol . Sorry if I was totally off topic

Sounds to me like you are just making big peat pots. You can buy those in 4" pot sizes, place your seedling in it and when ready just plant it peat pot and all into the larger pot. The roots will grow thru the peat pots and they will breakdown in the soil. If you try this make sure that you remove any of the peat pot that is not under the soil. If you do not do this the parts sticking above the soil will wick away water much the same as a candle wicks wax. Personally I just move the sprouted seed into the container that they will live in until harvest if they are Auto's that I grow in the greenhouse. But the photo's I start in the basement with my tomato plants that go outside get started in peat pots.