We've commented in the past about the lack of great Texas style -- real wood-fired -- barbecue in Dallas. But during the Posse's "Impromptu Best of Dallas BBQ Mini-Tour" Saturday, one conclusion was clear: Big D is raising its game. Over a period of about four hours, we ate at three joints. Each smokes with a different kind of wood. The Pecan Lodge at the Dallas Farmers' Market uses mesquite. Meshack's Bar-B-Que (OK, it's in Garland but we're counting it as Dallas) uses pecan. And Lockhart Smokehouse in Oak Cliff uses post oak. Admittedly, these three places were already our…