But it would not happen on any important scale as long as the phalanx would be able to keep its formation.
And any heavy infantry, swordsmen and pikemen alike are butcher once they loose their formation.
I see what you mean. Greater shield and often better armour.
On topic I thing any button drop the pike use your sword and the other way would be too much micromanagement for little gain in term of experience.
If your phalanx unit is forced to use their swords instead of their pike on an important scale then their formation is lost and they should not hold 10 seconds before rooting.