The result, credited here as the Barbarian mix, is less a remix than an exorcism. Where the original take apparently simmered, this one arrives at a rolling boil from the first bar and refuses to cool. You can hear the room in it — the sense of a band who have played this song live a hundred times and finally decided the studio version should sound like the gig, not the other way round. That's a rarer instinct than it should be, and it pays off handsomely.

The engine of the thing is Brian Petch's guitar, which doesn't so much accompany the song as argue with it. There's a real physicality to the playing — detailed without ever curdling into fuss, aggressive without losing melody — the sort of guitar work that used to get bedroom obsessives reaching for a four-track in the eighties, and which still, mercifully, sounds like a human being wrestling an amplifier rather than a plugin doing the wrestling for them.

Over the top of it, stayMellow turns in a vocal that's the real coup here. This is a singer who understands that ambivalence is the hardest emotion to sell convincingly, and he sells it: the range is considerable, but it's the control that impresses, the way he can let a line fray at the edges exactly when the lyric needs doubt to creep in. Because doubt is the whole engine of the song — "Hard To Leave You" isn't interested in the easy catharsis of the breakup anthem, walking-away-triumphant, door slammed, better off without you. It sits, admirably, in the much harder place: should I stay, should I go, and what if I can't tell the difference between love and habit anymore? That refusal to resolve is what keeps the song interesting on repeat listens, long after a more decisive lyric would have exhausted its welcome.

Producers Rob Whiteley and Paul Kinley — the latter also the song's writer — deserve credit for restraint as much as intensity. It would have been easy to bury a track like this under gloss; instead the mix stays lean enough that the synth-and-guitar interplay RISE have clearly spent years perfecting can actually be heard doing its work, rather than merely implied.

None of this is showy, in the end, which is rather the point. "Hard To Leave You" doesn't announce itself as An Important Song. It just gets steadily, cumulatively under the skin, the way the best RISE material always has — driving rock with a bruise at the centre of it, played by a band who sound entirely certain of who they are even while singing about being entirely uncertain of everything else. Difficult to leave alone, more like.