I'm a CHR programmer in Canada (not Astral) and the first single tested mediocre for us. We dropped One Thing after it tested dead last out of about 25 songs. It's not a hit.
Not popular in Canada? Odd! If it is popular here in the states, it usually spreads to the North! Unfortunately, it doesn't really happen the other way around...
Radio in the States has more room for over play of (non) hits, as long as the song playing is not a threat to a sister station.
Companies there can own up to 60% of a market.
Radio in Canada is still restricted to Two AM and two FM in a market.
As a result, it's harder to just play anything, justifying that it's played simply because it's music that is not a threat to a sister station.
(the above point is best maintained when speaking of songs that are chiming in as "Song 41" though.)