Is there a word or phrase for when someone says they can do something but it just so happens they can’t do it right now?
For example, if someone said that they could read minds but they couldn’t read your mind for some reason, what’s the phrase used?
I seem to remember it starting “oh how _____.”
You probably mean "Oh, how convenient." If I claim I can read your mind and I'm asked to prove it, I can give the excuse that your attitude is too negative and that it's blocking my special mind-reading abilities. That's a "convenient" excuse, for me.
“How convenient,” I'd say, “that everything you can't explain, you say was created by... God.”
"How convenient," they'd say, "that anything you can't explain with science, you say you can't explain... yet."
How to Survive in a World with Two Or More People, 2008
Perhaps you mean inconvenient?
It is inconvenient for them as it stopped them from showing you something, therefore making it harder for them to prove that they're not lying.
Alternatively, if they were just saying that they couldn't at the moment as an excuse, as they were in fact lying, it would be unusually convenient for them.
The phrase you were using appears to be sarcasm so I would assume it is the second interpretation.
