There is no lower limit. No matter how low, put it in a crock pot or other slow cooker and after a few hours, it's like butter... You just need to know what meal to use it in. I do mean muscle meat, don't get into other various parts pieces tongue brain etc whatever though I can be coaxed into eating liver a few times a year if enough mushroom gravy and roasted onions are included.
However, I do sometimes do "chopped steak", which is when you take about 1/3 lb, ground hamburger/etc, and in this case, the higher fat (cheaper) ground beef is better for once, and I have a piece of pvc sewage pipe (was not used for that purpose, lol), and I pack the ground beef into it very densely, about a 1.5" tall cylinder cut of that PVC pipe to form the patty, very dense (very dense being important), and grill that. I add whatever flavors I want, though for the consumption of other people, I usually only add some garlic powder and then let people decide what else they want if anything.
As long as you only cook it to medium rare, it's very good. Medium or more, not as much. That's just me, before it gets to medium it has a steak taste, after that it just tastes like a hamburger patty.
Adventurous cooks will massage in onion or peppers, whatever, but if you add too much high water content additives, then you will need either a grain to absorb it or some egg added to keep it together. It's not necessarily a meatloaf, rather a science experiment but it always tastes good when you add what you want, specific to your tastes.
I realize the topic intent was steak cooked whole, just saying there are more ways to cook a piece of meat, ignore my reply if it doesn't suit your needs. A whole piece of HQ meat, I want to cook out on the grill but in winter, I can make trade offs.