Pike Creek Turf has a great page on their website dedicated to Bermudagrass renovation. You might pick up a point or two from it.
http://www.pikecreekturf.com/renovation.htmlI have found that allowing for regrowth by promoting the regrowth to occur through fertilizer and normal irrigation cycles has provided acceptable control of the underlying grasses. Often, Superintendents will spray once, shut the water off(why water dead turf) and expect regrowth to occur naturally. This causes the plant to enter dormancy if rainfall does not occur which severely limits regrowth and uptake of the herbicide on the next application. Promoting regrowth with applications of ammonium sulfate along with routine irrigation allows for a better kill on the subsequent sprays. Normally, you want to wait 21-28 days between sprays, however this is not always an option. Round-up, Fusilade and a good penetrant are the norms when not using a soil fumigant like MB or Basamid, yet still only control 96% of the existing turf.