While aiming a Straight Arrow you can cancel the attack by going into EX mode.
In other words, holding down the  button to aim and then pressing the R button will cancel the Straight Arrow.
Has this been discovered before? I didn't see a thread on this so I thought I'd mention it. It could be a decent way to get a shield bash in.
Are you sure? I could swear I've gone EX Mode mid-Straight Arrow before.
Pretty much anything where you can hold the button to charge or w/e can be canceled
My age exceeds your IQ...significantly
Can you think of some scenarios when this could be useful? I'd like to implement this into a strategy if possible.
Go EX, dash towards the enemy, Swordslash?
There's really not much you can do. They were expecting a projectile attack, so what are you going to do? Try to get close enough to trigger one of his ground moves & hope they don't realize what you're doing?
Honestly, the most viable plan sounds like your Shield Bash suggestion.
It could also just be useful for mindgames. If the opponent decides to use your straight arrow as a chance to attack then it's perfect timing for to stop their attack and counter with something, maybe even weapon master.
Interesting...I should try that some time.