Is It a Good Fit?

Alright, you experienced saddle fitters out there in the blogosphere.  I need your opinion.

I purchased my new Tucker Cheyenne Springs trail saddle for two reasons:

1)  My "dream" saddle, a Hereford roping saddle, at close to 40 pounds, was getting too heavy for this old body to heft onto a horse.  Although I liked it's heavy-duty construction and full rigging, it was really a case of overkill for the riding that I do.

And, more importantly,

2) The Hereford had a semi-Quarter Horse tree, which it became evident was too narrow for either of my wide-bodied girls.

Kate developed patches of white hair at the top of both shoulders, indicating that the saddle was pinching her there, preventing both sweat (she would have a little dry spot there on an otherwise wet back) and circulation (hence killing the hide's color-producing cells). (By the way, it seems I switched saddles in time to prevent permanent damage:  this spring those vague white patches shed out with Kate's winter coat, leaving her dun coloring intact.)

Maddie is white on both shoulders, so the color-change wasn't there, but the lack of a proper sweat pattern was enough to cue me in.

So the Hereford went down the road to a [strong] young gal in Oregon who wanted to do cow horse work, and I began my search for a new saddle.

 I looked at various saddle designed for the middle-aged, female trail rider and ended up deciding on the Tucker brand, that was developed specifically for this particular market sector.  Because I have my English saddles if I want to ride in that fashion, and I have Paint horses to show/market in cowboy country, I wanted a pretty traditional looking western saddle.  The Cheyenne Springs fit the bill.

My friend Anita and I had hauled the girls down to Yakima earlier this year to make sure of the tree width to order, and put in my order.All of Kate and Maddie's rides this spring have been in the Tucker, with escalating problems with Maddie seemingly related to the dropped rigging necessitating a switch in girths.  But Kate has done well.
The only question I have is about the sweat pattern that developed after our ride last week in Robinson Canyon.  It was the most strenuous ride we've had this year, on a fairly humid day.  When I pulled Kate's tack off, here is how her back looked.

Her shoulders where the last saddle pinched were nicely wet.  The "tunnel" of the gullet was appropriately dry indicating plenty of air circulation down her spine between the bars of the saddle.  The thing that has me perplexed, however, is the dry area 2+ inches either side of that:  does this indicate that the saddle is "bridging" between the front and back, and not distributing the saddle/rider's weight uniformly across her back?

 

 This side (left) seems passable to me, but...

 

 ...her right side had an odd circle of sweat around the lower dry patch.

And the reality is that as Kate gets a little more fit (and loses a little more weight, though she's not as bad as last year) the "table" that is her back may become more sloped.  It will bear watching how this effects the saddle's fit to her back in the future.

What do y'all think?