Now that Frank Thomas has announced his retirement, there should be not one iota of debate over whether he is of Hall of Fame caliber. Yes, Thomas was a designated hitter, but the Edgar Martinez argument against induction just doesn't apply to the Big Hurt.
As Rob Neyer noted, for his first nine seasons Thomas was basically the closest thing baseball had to a modern Ted Williams. And his career numbers — achieved without accusation — rank him among the 20 most productive hitters that ever lived. The question is not whether Frank Thomas will be elected to the Hall of Fame, nor is it whether he should get in on his first try. The real question that should be pondered is how any knowledgeable baseball fan could argue otherwise and what it will say about the Hall of Fame voters when he isn't elected unanimously.
Since Ron Bloomberg made his famous 1973 at bat at the position, no full time DH has been elected to the Hall of Fame. Frank Thomas and Edgar Martinez are the two most often cited examples (by both sides) in the debate over whether a player who mostly hit DH should be elected to the Hall. While both should be enshrined, there is no real comparison between the two players. Admittedly neither could play the field, but Thomas was by far the superior hitter.
Frank Thomas: .301/ 521 HR/1704 RBI .419 OBP/.555 SLG/.974 OPS
Edgar Martinez: .312/ 309 HR /1261 RBI .418 OBP/.515 SLG/.933 OPS
Examining Thomas through a prism of "historically significant" statistics, Frank excels in every respect. His 521 home runs rank him 18th all time (tied with Ted Williams and Willie McCovey). And if you omit known steroid users, Thomas actually moves up to 12th on the list. Further displaying his immense power and production, Frank's 1,704 RBIs are 22nd all time, just above Reggie Jackson's 1,702. But Thomas' true staple was his completeness as a hitter, registering a career .301 batting average and walking 1,667 times (9th all time).
From a sabermetric standpoint The Big Hurt's prowess only grows. His .419 OBP is 21st all time, a further testament to his incredibly consistent ability to get on base. But more impressive, his .974 OPS ranks 15th all time and his 156 adjusted OPS+ ties him for 19th with Dick Allen (not in the Hall of Fame, but should be) and Willie Mays.
Despite his obvious lack of base running ability, Thomas' 2,003 career runs created rank him 19th all time, positioned right below Mickey Mantle and just above Ken Griffey, Jr. Thomas was the total package hitter — a rare combination of technique, power, and patience that formulated into one of the greatest hitters that ever lived.
Critics will always cite Thomas' "one-dimensionality" as a knock against his Hall of Fame credentials. For some players this may apply. But few have naturally posted offensive statistics like Thomas. The Big Hurt was far from one-dimensional. He simply saved his multiple dimensions solely for his plate appearances. Argue about Robbie Alomar and Edgar Martinez. But when it comes to Frank Thomas, there is simply no debate.