Nope. If I remember correctly, shaders are either compiled just-in-time as needed or when specifically requested by the program. Once compiled they are cached for as long as the program runs. Shader compilation can be a source of graphics stutter so they are precompiling all the shaders at program startup. The compiled versions do not persist past program exit. This is not something ED can change as the functions to compile shaders are not their code. If it's taking long enough to be frustrating for you at startup, just imagine what it would be (and was, prior to 1.3) doing to your graphics performance if it happened piecemeal, in the background, ingame and taking up your graphics processors cycles that should be contributing to your framerate