I always feel tests are a false, manufactured opinion. I had had lots of mercs, bmw and lexus before I bought my late, much lamented ls400, a car I considered dynamically inferior to the marques mentioned. And...this may be the case...you can argue that a bmwis more involving to drive, a jag is prettier, a Merc has more gravitas....but I don't think any of those manufacturers made a car with the blend of attributes the LS has. It's only when you LIVE with a car you appreciate its quality. To make an analogy, for roadtesters it must be like attending a a series of parties and meeting a load of strangers...and judging them on the brief time they spend with each stranger. Obviously the more charismatic, more idiosyncratic, best looking , will stand out...will be remembered....
For me, an ls400 can do everything all its competitors could do...but its blend of attributes are, and remain, unmatched. I have said this before but i don't think a car with such mechanical integrity, such impeccable manners, such tactility and such a resolved, coherent design has been available to the public before or since.....to continue my analogy, the ls400 CAN party, but it gets you home safely too....and then looks after your hangover...day in, day out....