removing large leaves now or later?

You're never gonna convince a leaf worshipper that defoliation has benefits. Don't waste your time trying. It's a greatly misunderstood technique, by both people who are for and against it. Personally I think it really has less to do with light than airflow. Cannabis is a wind pollinator, it certainly seems reasonable that flowers that get better airflow would have better chances of catching pollin and get more attention/resources. That holds true even in your top canopy, buds like elbow room. I think it just gets spoken of in terms of light because you can't really visually see airflow. Regardless of the larf bud density debate, it's reasonable just for preventing mold, mildew and budrot. I don't care how cherry you think your environment is, in the middle of a thicket you're gonna have a moist microclimate. You would practically have to strip a healthy plant naked before it reasonably impacted your grow. If you're feeding your plant then stored sugars aren't an issue and several other factors are gonna limit an indoor grow before leaf count ever enters the picture lol. If you're new to trying, start slow. It's easy to come back and remove more leaves tomorrow but you're not gluing any back on. Start from the bottom and work up, targeting large fans. Just removing the fans from the base of branches can make a big difference. Leave the leaves at the top few nodes alone unless it's a real cluster f, those are the leaves doing the heavy lifting since they get the best light.

In cannabis plants, natural sugar production is always happening, where larger amounts of sugar are key to a larger yield. Newer buds are the workhorse leaves, producing the sugars that older leaves store. This sometimes creates a competition for sugar amongst the leaves of the plant. Healthy plants do not need much alteration, but weaker plants sometimes need the extra sugar boost. Many growers use tricks such as defoliation to trim older leaves so the flow of sugar can reach other less mature buds. Others will add extra sugar to the plants to intervene with the natural production and help it along. 

Buds are flowers not fruit. They have there own leaves to produce there own localised energy. Hope this helps.. Peace and love

A few comments I found online... Take from it what you will I don’t know how to say this…. But fuck fan leaves. I’ve found you can grow bigger, denser buds throughout the plant with removing them, heavily, multiple times throughout the grow. It helps airflow get through, reduces chance of mold and the plants are happy as fuck. I suppose if you have 3000 plants though, then fuck fucking the fan leaves, but for a 4x4 it pays dividends. I agree with this. I remove any large fan leaf that prevents light from reaching lower buds, especially when heavily in flower, and it helps with preventing mould. Science indicates that it’s mostly only nitrogen that is mobile between these leaves and the rest of the plant. That’s why they go yellow. I agree, I defoliate fan leaves heavily after the final stretch and throughout the flower cycle. Super beneficial in veg to leave them but in flower I have seen no benefit in leaving them in my own personal experience. Everyone’s style or grow tek varies though as well as growing conditions so what works for me may not work for someone else.

Ich würde sie auf jeden Fall entfernen. Ja du wirst hier immer pro defoliation oder gegen defoliation finde. Ich persönlich habe bessere Erträge seit dem ich entlaube. Die Buds werden dicker und die Pflanze hat bessere durchlüftung. Und ich habe es lange im vergleich versucht die gleichen Sorten mit und ohne gleichzeitig zu züchten am Schluss haben die entlauben immer mehr Ertrag gehabt. Und waren oft gesünder. Ja in der Natur machen es die Pflanzen nicht,aber du willst ja mehr Ertrag, in der Natur will diePflanze nur besamt werden und in der Rest der Landwirtschaft werden die Pflanzen auch behandelt wie die Tomaten die werde. Auch entlaube. Viel erfolg

No, unless extreme high humidity is impossible to control. Buds do not need direct lighting to grow. More leaves = more energy being made = more (bud) growth.............it is that simple. Less leaves = less energy being made = less (bud) growth............it is that simple.

Remove those and keep the leaves. More leaves, more Bud. Buds don't need light, they use the sugars FROM the leaves to grow...

yea you need more airflow there