Here's some researched info that you may find interesting:
From the book "Good Neighbors: Companion Planting For Gardeners" (Rodale press)

Page 319

There have been studies done showing intercropping of with snap beans, peas or cabbage produces less total crop production BUT the quality of the crop produced was BETTER!

When intercropped with peas alone the peas performed better than when grown alone (monoculture).

There is also a note about potentially allelopathic compounds in tomato roots but no information on what this compound affects.

The only other thing I can think of is that Squash and potatoes are not recommended as companions and the same for onion (alliums) and cabbage families.

I have not seen research to state that you cannot plant as you are desiring so I say "relax".

Louise Riotte's books "Carrots Love Tomatoes" and "Roses Love Garlic", both on companion planting are pretty good on information though they seem to be a bit short on research testing information so take them with a grain of salt.

"There have been studies done showing intercropping of with snap beans, peas or cabbage produces less total crop production BUT the quality of the crop produced was BETTER!"

That's good to know. I'm not too concerned about total crop prodution, as I always overplant my needs. I figure that way if I have a bad year, I should have enough. If I have a good year, I get to share. If I have a great year, the neighbors hide from me when they see me coming with my garden basket, and the local food shelf gets the extras.