With Technic Launcher, impossible. The Modpack installer can choose not to install optifine.Alas, I'm still having problems. Is it possible to not start the Optifine mod in Technic? I believe that was the current issue on Macs.
Perhaps this isn't the best place to ask, but is there a way to keymap skills without using Technic?
With the modpack installer, if you selected to install Macro Mod, you can keybind skills.