Tilden not only would have been a potential contender for majors but in his prime he probably really would have been by far the major contender. You could even joke there were no contenders outside of him. It would probably be Tilden versus the rest of the field. Most likely the rest of the field would lose. I think there was a super chance Tilden would have win several Grand Slams and I would tend to think Tilden easily would have won over twenty majors. In his best years he won around 98% of his matches. Over his career, including the many years he was losing Tilden still won over fifty percent of his tournaments entered. His record is arguably as great as any, possibly greater than any player. Tilden has every stroke. He had a great forehand, excellent backhand, a great serve, super movement and excellent stamina. His volley was okay but not great but he did win many a doubles titles so it was fine. He was also obsessed with studying the game. He was about 6'2" tall and I have no doubt if he played today he would have adapted easily to the tennis of today.