Scrub potatoes, pierce several times, and roll in warm salt-water mixture. Let dry on a rack.
Heat smoker to 275°F and smoke potatoes until they reach about 200°F internally.
Increase heat to 375°F, brush potatoes lightly with oil, and cook until they reach 205–210°F.
In a skillet, cook bacon until crisp. Remove and reserve.
Leave 2 tbsp bacon fat in skillet. Add onion; cook until soft. Add cabbage, garlic, and spices; cook until tender. Return bacon and toss.
Whisk mayonnaise, chili sauce, green onions, relish, horseradish, parsley, mustard, and Worcestershire until smooth.
Heat gently in skillet or reserved braising liquid.
Cut X in potatoes, squeeze open, add Swiss cheese first to melt, then cabbage mixture, corned beef, more cheese, and dressing.
Plate immediately while hot and melty.
