I think that his musical vision for,& marshalling of, the group in '88/'89 was absolutely crucial to their subsequent success & to a point that many Roses' fans are possibly unwilling to accept. Yes, there were the demos but they were rough diamonds. Yes, there was the will & ambition & neither of those qualities or the songs appear to be present now, but I think Leckie was the factor that tipped all that over into greatness. Albeit for a brief moment.
By the time of Second Coming he'd lost his authority with the group. He could no longer channel them & that was it. TSR was a result of a combination of elements coming together. This was less about the Roses as a band in the conventional sense & more about a moment built on personalities & creative visions temporarily gelling. And not just between the band themselves & Leckie but the dovetailing with a generation of fans in terms of cultural reference points, drugs & attitudes. Needless to say, this was never going to repeat itself a quarter of a century later. Even on a minor level. It's amazing it happened once.
As far as the reunion goes. It was fun. I don't regret them doing it. I'd go & see them play the same set again if they choose to.
Whatever they had back then, there was still a piece of that this time around, but another great album or, indeed, any kind of album was never going to happen.