it would be very nice, because sometimes you are working on something that requires something to do something every tick, and it spams chat, but you also need a different commandblock, to test something out and you need its output, but you cant see it because that output from commandblock 1 is spamming the chat
The Meaning of Life, the Universe, and Everything.
I see what you're going for. This already exists, after a fashion.
First, have your purple repeating every tick command block with its testing command...
Next, have a chain conditional command block hooked up to it with a command that makes a redstone block 2 blocks away...
setblock ~2 ~ ~ redstone_block
Adjust coordinates depending on which direction you are facing.
Now on top of that redstone block, put a regular command block with this command...
setblock ~ ~-1 ~ wool 14
The redstone block won't change until the testing command fires at least once.
Now put the commands you want the tester command block to fire next to the redstone block. The first must be a regular one requiring redstone. The others in the chain must be chains requiring no redstone.
That disables the output box that says if it succeeds. The OP is suggesting that, for example, if you have a /say command on a loop, you can press a button in the command block GUI to mute that one.
I just tested it, and you're right. Well, if that's the case, then the feature that the OP requests should just be combined into that button, as I don't see a reasonable instance in which you would need the two to be separate buttons.