Dcarol,
In pointing out where you were from (i.e. a "wee bit south" of Linn), I am pretty sure Thom was saying you were from England, and was not trying to identify you as being from the Southern Uplands or Northumberland rather than Yorkshire or parts south. He was trying to provide you with a point of view originated from your side of the pond rather than you having to rely on a bunch of Ugly Americans who you seem to think have it out for you.
"How on earth can you isolate one component when listening to a whole?" Probably the same way that you can identify differences "as long as all the cartridges are played in the same system." Many of us have experience with isolating portions of systems. Many of us have heard your table/arm with a cartridge, and then heard that same cartridge with other tables/arms and come to the conclusion that upgrades can be had on the arm.
Just because that is someone's advice does not in any way belittle your desire to change carts. Heck, I've bought carts at times because they were cool-looking (and they had a reputation for sounding nice). I apologize to noone. I knew what I was getting into and I was curious (and most of those I have sold). Having no good reason at all for changing carts is fine. Don't let anyone tell you otherwise. What I think almost everyone who has critiqued your path (in ways you seem not to like) has come up with is precisely the concept that Linn promoted. The thread Thom notes is one of many in the archives which comes to a similar conclusion. The isolation/table/arm/phono is a platform upon which one mounts the transducer. In this case, people are saying you are not giving your transducer the chance to show its best. The corollary to that is that whatever cartridge you end up buying (because in an otherwise fixed system, you prefer Cart B over Cart A), you will also not be able to have Cart B show its best. I don't think anyone on this thread has questioned your opinion, whether it be based on present experience or expected experience, that Cart B is going to be better to your ears than Cart A. People are just suggesting putting the horse before the cart (pun intended; stupid grin).
I for one would be interested in two followups:
1) what you find out at your dealer (if the system makes the XV-1S sound better than it sounds at your place, and if on that system, the A90 sounds better than the XV-1S).
2) what you find out when you put it into your system (did the same comparison hold true? (note: personally, I find it very difficult to be objective about a new cart I am excited about early on in the post-acquisition process if I go into it thinking it is going to be better; if I generate preconceptions, unless it is super clear-cut, those preconceptions have their own weight).
Good luck!
