The facts: TNT and Dan both made their debut in Star-Spangled Comics #7 (1942), already a twosome, no waiting. The "human hand grenades" lasted as a feature in that book until issue #23 (1943), with one appearance (actually their second) in World's Finest #5, a story reprinted in 1973's 100-Page Super Spectacular. The duo next appeared in Super-Friends #12 (1978), and from there, in a handful of All-Star Squadrons. They were created by Mort Weisinger.
How you could have heard of him: Dan the Dyna-Mite was a headliner in Young All-Stars, the first issue of which violently killed his adult partner (Axis Amerika's Valkyrie did it). In the 90s, Dan appeared in James Robinson's The Golden Age, his body taken over by the Ultra-Humanite, and in the early 2000s, was shown to be a member of Old Justice (in several issues of Young Justice) and one of the 7 Soldiers of Victory massacred massacred at the start of Morrison's project, as Dyno-Mite Dan (though I believe this was someone else under the mask). DCU: Legacies #2 (2010) makes TNT and Dan founding members of the original 7 Soldiers, apparently replacing the Golden Age Green Arrow and Speedy on that team.
Example story: Star Spangled Comics #15 (1942), "The Log of the Lucky Lode", art by Louis Cazeneuve, writer unknown
1) Murder is okay if it's to make a crib for a baby.
2) The hermit only calls certain trees his friends; those acorn-holes in Lost Valley can go to the wood chipper for all he cares.
And 3) Dan's puns are just the WORST.
Who else? That was all in the past. I'm next looking to the future!