Bunnyears: I don't doubt your sincerity, but I have never read any reference in any Mahler bio or music study relating the sleigh bells to a sleigh ride. We also know that in its initial printing, Mahler indicated mm = 88, and then later wanted it slower, which Maazel is.
You mention weird tempo changes and rubatos: they're in the score. That's where many conductors go wrong is that they ignore (or don't understand) Mahler's meticulous notes to conductors. What may really annoy you is the simple fact that many conductors don't handle it smoothly or "organically' as musicologists like to say. Worst are those who want to turn it into their own vision and rip the music all over. This is why I can't understand the general adulation given Herr Rattle. Reading the score following his recording is very revealing. That's where people like Maazel stand out. While he can be a very infuriating conductor, when he wants to, he can be brilliant. In Mahler's case, what I love about his set is the attention he gives to the details in the score: string and wind portamentos are not left out as most all modern (after 1950) performances do. Why? Portamento was the standard way of playing at the fin de siecle, but became outmoded. When a conductor asks for it, and the orchestra has the skill to do it, the differences are very telling. Most people now find portamento slovenly and ugly: like a bad night club singer who always scoops notes. But when Mahler writes it into the score, it must be played. When he writes "faster here" followed by "suddenly slower" it must be played.
When I judge any recording or performance, the standard is always the printed score, tempered of course by common sense and tradition. This is one problem I have with so many people this board: I greatly enjoy the opinions, sparring, etc, but as one who reads music fluently, and studies it seriously, I have issues when people select their best recording without ever having considered the composers intention.
Where Maazel screws up: he clearly misreads Mahler's intention in the last movement. At his slow tempo, any sense of innocence and child-like quality is hopelessly lost in the bog.
In short, I don't give a damn about a conductor's vision: I want Mahler's vision. I want the conductor to play what's on the page, not get in the way, and let the composer speak. Very, very tall order. With Mahler, conductor egos run full throttle, and too often Mahler loses.
Well, off to a live M2. Huge choir assembled. Should be awesome.