The LWJGL release tries to cater for the needs of as many ppl as possible with the single release, this includes noob's and pro's. Splitting up the native jars will make it more difficult and cumbersome for people to handle (especially noobs) as you'll have to manage almost twice the amount of native jars. Also remember not currently possible on Macs as they use fat binaries. The current release IMO strikes is a nice balance between easy of use and download size. I suppose if its something thats really needed then another folder can be added to the applet download package that contains split up signed natives.