Are you seriously going to imply that this was a deliberate game design choice? That they did this for balance reasons or something along those lines.
As a matter of fact, Yes , DMC 4 has aerial moves that uses left analog stick inputs and to continue comboing in air , we need to be faster with inputs than on the ground. Eg: Ecstasy(Dante) and Calibur(Nero). We can't have the toggle if player accidentally clicks the left analog stick while performing these aerial moves cuz that would drop the enemy and aggrevate players.This goes by default controls and we can't expect the player to change his control scheme and map his lock-on toggle to another button. I would rather not have it all cuz it really has no major purpose unlike DMC 3 which didn't have aerial moves with left analog stick.
To further prove the absurdity of your defense.
Pssshh...This whole subject of lock-on toggle on the move being an issue is absurd.
You can toggle just fine
Well duh...I think we have established that.
We can toggle enemies while locked-on. But your issue is not being able to toggle when moving while locked-on.
This is not a DMC3 vs DMC4 design contest.
You made the comparison with DMC 3 and wanted lock-on to work exactly the same way as DMC 3.Its like expecting resident evil to behave like any other shooter game where we can run and shoot at the same time.
The way it should be is the way it is in every game with lock, just like It was in DMC3, this is a flaw in the game's coding.