I've found a few interesting links on using NGEN as a final step in an installer from this post. Is there a reason it is preferred to NGEN your assemblies at setup time, instead of at build time? I'm not particularly concerned with setup time, but it just seems like an unnecessary step that could be automated by my build.
NGEN output is computer/CPU specific. your build machine will probably not be the production machine (maybe different DotNet version, AMD ? INTEL... who knows..)
来源：https://stackoverflow.com/questions/1779093/does-it-make-sense-to-distribute-pre-ngen-ed-assemblies