London Broil, take 1

I went to the grocery today looking for dinner ideas and ended up coming home with meat to make london broil. I had never made it at home before myself, so I figured it could be a new experience like making the pulled pork the other night. As soon as I got home I looked up a few recipes on Epicurious.com and couldn't find one that was especially right. I decided to use both recipes to improvise a marinade. Mostly it had oil, vinegar, herbs, and garlic - pretty standard stuff for a beef marinade, I thought. After letting it marinade for a few hours I decided I was ready to start dinner. This is where the second issue came up, all the recipes I looked at gave different cooking times for the meat on the grill each saying they would produce a medium-rare slab of beef as thick as mine. I didn't understand how the same thickness of meat could have such a variety of cooking times on the grill to supposedly get the same results. So, I just decided to compromise again, going for 10 minutes a side on medium heat, plus one extra minute on high heat to sear the meat. That seemed like a conservative cook-time since some suggested 15 minutes a side, and others 8 minutes. In the end, the meat was flavorful and juicy enough, but cooked a little more than I would have preferred. I would make it again, but I would cook it less time, or consider doing it in the broiler like it said to do in a 4th option. Anyway, I ate it over a bed of mixed greens with broccoli and red onions in a parmesan cream sauce on the side.