Hi HAL,
With meat that is minimally cooked, quality is critical. If It's tough to start with, it's not going to get any better. Any steak cooked well done is likely to be tough too.
Another strategy is is to start with something that is normappy tough and cook in a manner that will make it tender. This is the basis of smoking brisket, ribs, pork butt... I did some corned beef brisket points yesterday. They come off the smoker at 165° and go into an oven to finish. I like to taste them when they come out of the smopker (because I can't wait
) but hoo boy, are they ever tough! After a couple hours of moist heat (covered Dutch oven with a little beer) they cut like butter.
Keep trying!
Edit: I thrrow steaks right on the charcoal too. Special people I cook steaks for (SWMBO, fishin' buddy) specifically request this technique. I also buy ribeyes at Sam's Club because they are good quality.