Hey gamma016! With all due respect for my colleagues that answered you before, but I'm pretty convinced you cannot use the Split Fire special rule on the attached commander
1.) The rule granting all the special rules is bound to the formation, which the attached commander is not a part of.
2.) This Rule " Enhanced Tactical Responses" quotes: " All Drones
in this Formation
have the Interceptor, Jink, Outflank, Precision Shot and Split Fire special rules." So it specifically affects only the drones and only from this formation.( Vice Versa the +1 BS from Collective Targeting Data that is specified to affect all Drones in the army)
You already recognized that your commander needs EWO for Intercepter, which he is not granted by the formation for of not being part of it. I'm afraid the exact same thing is true for Split Fire.
But you can give the Commander EWO and Target Lock, which would have the same result as Split Fire for +5 points. What was your Idea behind joining the drones with the commander?
I looked up the official GW FAQ from Nov 16, in the Independent Character Pat its says:
"Q: Do rules applying to ‘the unit’, such as those from Formation
special rules (e.g. the Skyhammer Annihilation Force), or unitwide
special rules such as Dunestrider from Codex: Skitarii
apply to any attached Independent Characters?
A: No. The Formation special rules themselves do not
apply to characters that join the Formation (unless
specifically stated otherwise), although they may confer
other special rules which do apply to characters that
have joined units, such as Stealth or Stubborn."
DecsUse the edit button instead of double posting. Cheers! -L'R