Shirou =/= Archer (EMIYA).
Q: In Saber Route, Shirou did not encounter Archer's Reality Marble "Unlimited Blade Works" and certainly did not learn it. If he were to train and attempt to develop it by himself, how long would it take?
A: Ten years to master the basics, another ten years to become proficient at it.
... something like that.
Shirou&Archer can't swordspam outside of the Reality Marble like drops of rain or like a machinegun. Outside of RM, they can "create" ONE WEAPON AFTER ANOTHER AND PREPARE DOZENS TO USE LATER, in other words, is like a gun (shoot, reload, shoot, reload, shoot, reload), not dozens and dozens at the same time and firing them mercilessly like a living GoB (shootreload shootreload shootreload shootreload). The only moment that was clearly seen such move, was in Carnival Phantasm (not canon, only comedy) during the race while Archer was trying to attack Gilgamesh.
By the way, Nasu stated that Shirou and Saber only became victorious over the 5th War, because THE POWER OF LOVE, in other words, protagonism. ONLY THIS.