Just because you streamlined your solution during the design phase doesn't mean it's going to react efficiently across a LAN or WAN. You also need to optimize your hardware and network on your FileMaker Server machine. Hardware and networking are usually secondary to proper design but it can make a big difference in how your solution performs if you have sub par equipment. There are so many factors that play into how a solution performs that it's nearly impossible to provide the right answer for everyone. Instead, what I have here is a cheat sheet that will assist you in resolving speed issues.