There is a BIG fucking difference between looking at a row of plants and choosing which one looks the best or tastes the best and growing that next year versus making a frankenstein monster of starfish, grasshopper, and tomato.
How about taking a row of plants, irradiating them with high doses of radiation or watering them with potent chemical mutagens and then selecting the best mutants? Cause that's how the modern cultivars are made!
Oh, and in this case you don't even need to test them - just make sure that seeds don't glow in the dark and you can sell them. With whatever induced genetic defects - like lowered protein content (modern wheat) of almost dysfunctional fat-producing genes (corn). Oh, and during these manipulations your plants sometimes might acquire foreign genes from bacteria, close-related plants, viruses, etc. Hope that's OK.
"Experience has proved that some people indeed know everything." -- Russell Baker