Sadly I've never won a treble.
I've only won the Cup twice in 12 seasons; First was in my first season, and the second was in my 10th season, in which due to some seriously strange results, I came second in the League.
I don't think it's very common at all, the Cup is hard enough to win on it's own.
I'd say League/CL Doubles are FAR more common, as this is very easy to achieve with a token bought/farmed team.
In regards to a 26-0-0 season, the best I have managed is a 25-1-0 season, it seems that the inevitable 'troll' result you get at least once a season ruins the chance of this.
It seems to me that the teams that are capable of winning trebles consistently are either:
A) Perfectly sat within a quality bracket in which they play teams that are very similar, or even lower in quality, in which management skills decide the winners.
B) High enough in quality that they can effectively 'steamroll' opposition, ie. Triplette/July Fourth.
That's just my opinion anyway![]()