Adq
That is why I need option to switch Click+Drag and Alt+Click+Drag behavior. In one state it works like now, in other Click+Drag draws and moves, Click draws, Alt+Click+Drag draws and change duration
You're referring to the Draw tool, right? Because you couldn't have the Smart tool create a note every time you click or you couldn't do any editing. Besides if you're talking about changing the Smart Tool state to the functionality of a different tool, that's going to take one or two keypresses. Hitting a function key to switch tool states takes only one keypress. So I'm going to assume those are keyboard shortcuts you want for the Draw tool.
I think based on everything you've said so far, this would be your feature request for the Draw tool:
Change current Click+Drag shortcut from draw series of notes to draw single note and move, create new Alt+Click+Drag shortcut to draw a note and change duration (i.e., current Smart tool default function).
However note that when using the Draw tool you could do the same thing as your Alt+Click+Drag with:
F5+Click+Drag
...to draw a note and change duration.
Either way, it's one keypress to get what you want.
Returning to the alternate state would differ. With your keyboard shortcut, releasing the Alt key would revert to standard Draw mode. With what I describe, hitting the F5 key would revert to standard Draw mode (remember that F5 toggles between the Smart tool and whatever tool you used last, which in this scenario would be the Draw tool).
You could argue that it's easier to release a key than to hit one, but the big tradeoff is that people might not like having the ability to draw a series of notes taken away, because that's one aspect of what the Draw tool is all about. Remember, that's how it works with automation, so it's conceptually consistent. If you want to make this feature request, it would be important to make people aware of what they would be giving up in the process.
Did you find out what Smart Tool Alt+Click+Drag does? It does something strange, sometimes nothing, sometimes note duration are jumping, especially with snap off, looks like a bug.
I assume you mean right-click, yes? It works as described in the documentation except for one error - where it says "drag to perform the alternate mode of the selected Erase tool" it should say "drag to perform the Mute mode of the Erase tool." In other words, it does only mute functions, not erase. However, remember it follows the rule of the tool. With mutes, you can't just draw a rectangle around notes. The mute tool has to touch a note to mute it. A confusing aspect is that if you hover over a note with Alt held, it will show the Scissors tool because that is the default behavior for a left click. However as soon as your right-click, it becomes the Mute tool.
Finally, I assume you know that Alt+click with the Smart tool causes it to act just like Draw tool, with the note duration being the same as whatever note you clicked on last.