I am not a farmer, just a gardener.... I tilled my beds the first year, and never since then. Every time I pull out a crop and plant another (2-3 times a year), I loosen the soil with a fork and plant. I have done the lasagna method you describe with the cardboard. By spring it will be rotted in. No need to till in my experience.

I agree with the above. Disturbing the soil unnecessarily ruins the structure.

Here is a link that might be useful: An excellent, brief tutorial about soil microbiology

Be careful throwing around words like unnecessarily. You don't know if it's necessary or not, given what was shared. It's not instant in a season, unless what you started with was fairly close. What you start with matters, and fixing the soil structure by tilling organic matter in can save you years in terms of natural methods. The pertinent questions are related to how well the sod was growing. If it grew well, skip tilling. If it was scraggly grass on clay hardpack, tilling will be quicker. Being adjacent to fertile soil will help. It takes years or decades for shrubs to take over from grasslands on clay. Layering compost is like adding time directly, so how long it takes still depends on how far you need to go. You can do it all at once, but there's easier ways to make a raised bed.

My guess is light tilling is going to be best for this first year, since you are trying for sales level production as fast as possible. Till, retest, amend, and next year you will likely be ready for no till. Sink a spade a foot deep and look at the soil at root level to decide.

I wasn't making making a decision on necessity of this particular instance. TY for clarifying if it sounded like that's what I meant.

The OM retained from the decomposing grass and roots are part of the benefit of using a smother method. I would prefer to till vs. removing the top soil where any possible micro-activity is going on, especially with the current decomposition you've made possible by smothering. Tilling OM into the soil could cause issues with chlorosis initially. Something to keep an eye on if/when it applies, but often considered a hurdle worth jumping when it's decided that a spot needs to be tilled to be able to dig in it initially. Ungardened ground can indeed be as hard as a rock.