"whenever you could" is a correct and usable phrase in written English.
It is typically used to express a situation or action that can be done at any time or whenever it is possible. Example: "I always told my grandmother that she could call me whenever she could, even if it was late at night."
Netflix paid handsomely to show you any episode of Friends whenever you could possibly want to watch it.
That was only possible because for three years you, your families and your friends have been donating £5 here and £10 there whenever you could afford it".
"Growing up where I did, you played whenever you could, and we got used to a lot worse than this," he said, referring to Bethpage.
"Whenever you could get Republicans who supported you, it was important, and the more prominent the Republican, the better," said William Maloni, a senior vice president at Fannie Mae until 2004.
And now, before Gross, you could bring an age discrimination suit whenever you could show that age was one of the factors an employer considered in choosing to fire you.
And it is easy to see why, if you were a child forced to take Mandarin and play the viola and learn the art of feng shui at the expense of ever just going out on some monkey bars, you would enjoy Lazlo very much, whenever you could sneak away to watch him.
It may seem like a weird way to get there, but a drone companion you can dismiss whenever you want could be how you replace even more traditionally smartphone-based activities with something less omnipresent.
Whenever you drive, you could easily kill a number of people by ploughing into a crowd.
Whenever you believe you could be using a better word given the circumstances, consult a thesaurus.
"Whenever you bought something, you could make a ton of money," he said.
Whenever we met, you could hear the creak of knife-blades opening in our respective pockets.
