An Italian sweet-and-sour sauce made with vinegar, honey, and raisins--agrodolce, literally "sour/sweet"--softens the bitterness of radicchio and escarole. Serve this salad right away, while it's crisp.
In a small bowl, combine vinegars, honey, 1/2 tsp. each rosemary and salt, and 1/4 tsp. pepper; set aside.
Heat a 12-in. frying pan over medium-high heat. Season steak all over with remaining 1/2 tsp. each rosemary, salt, and pepper, then rub with 1/2 tbsp. oil. Cook steak in pan, turning once, until medium-rare, 8 to 9 minutes. Transfer to a large bowl and tent with foil.
Reduce heat under pan to medium. Add remaining 1 1/2 tbsp. oil and the shallots; cook, stirring often, until softened, 2 to 3 minutes. Stir in raisins, then add radicchio and vinegar mixture. Cook, stirring occasionally, until radicchio just starts to wilt (wedges will break apart), 2 minutes; with slotted spoon, transfer radicchio to bowl with steak. Add escarole to pan and cook until it's barely wilted, about 1 minute. Remove from heat.
Slice steak crosswise, trimming fat, and return to bowl with radicchio mixture. Add escarole, pears, and parsley; toss to mix and transfer to a platter.