Two years ago, I marinated two gorgeous London Broils, and I figured I would do one with Teriaki sauce (Sons Favorite) and the usual oil and garlic and a shot of lemon juice. No salt because the Teriaki Sauce was salty enough.
The other, I marinated with oil, wine, lemon juice; smashed Juniper berries, and black peppercorns and Kosher salt.
I figured I would prep and do this like 4 or 5 day's ahead of time. On the 2nd day, DW said,"Hon, That meat has got to go into the freezer or it will sour!"
Well I took her advice, and set them in the spare refrigerator / freezer in the freezer section which is just a 20ºF lowest temperature. ( That's the way older refridgerators were made years ago ) ...
3 days later, I pulled them out and counter thawed them. They were the best London Broils we ever had. I would think the freezing together with the marinade really imperviated the tissue of the meat. I didn't even spike the meat either.
I've done London Broils with the same recipe, and without freezing, but they did not compare to the ones I previously prepped and kept frozen.