Fresh results were strong where it matters most. But the valuation question still looms.Last Thursday, Costco Wholesale (COST -2.92%) reported impressive fiscal fourth-quarter results, with both revenue and earnings per share exceeding expectations. The membership warehouse retailer continues to lean on a high-renewal, fee-driven model that makes its results unusually predictable, even when consumers are cautious. Shares were roughly flat in after-hours trading as investors weighed a premium valuation again ...