Let me ask a question...........(I am NOT a cycling wrench-person)
Lets say you had your LBS put on a new cassette (different than the one it replaced) and you made a point to have them index your gears, correctly. Well, first ride - you realize they missed the boat, badly. It was so bad I stopped and just turned the barrel adjustment in "A" direction (I had a 50/50 chance of it getting better). Well, I turned it about 9-10 quarter turns.....and it now indexes perfectly.....except it won't advance to the 11-tooth gear.
My question is....is it possible the gears index differently, under load (i.e. when I'm on the bike) v. how they index when it's simply in a work stand? I'm questioning whether or not they just overlooked this.......or ...tried/failed.
So here is what happened... I have done this too, and I am a very good bike mechanic...
Your RD was adjusted pretty closely from the LBS. But, it was just a little off and tempted you. You tightened the cable one full cog worth, so now it shifts cleanly, but it is off by one. You need to turn it the other direction (screw the adjuster in) to loosen the cable again. If you turned it 9-10 quarter turns before, then turn it 11-12 quarter turns the other way. Then, it should reach the 11 tooth cog and be sort of close to shifting across the range.
Possibly. A common issue with indexing while on a work stand is the wheel not being properly tightened/positioned in the dropouts. Your LBS might have just popped a wheel on and did up the quick release when the wheel was a little out of position on the dropouts. They'd be indexing the gears in the wrong position and it would definitely throw off the limit screws.
A lot of LBS's will just get a student/intern or whoever has free time to swap cassettes and adjust gears as well, since it's such a simple job that it's a waste of a mechanics time. It could be the case with your bike. It wouldn't hurt to address it with them, but I think the overall lessen here is that it's easier to spend $20 on a chain whip and cassette lockring tool and do it yourself. If you change your cassette once you paid for the tools yourself and it only takes 15 minutes of youtube videos to learn how to do it properly.
Of course, then you don't have anyone to blame/sue if your bike doesn't perform.
It sounds like the adjustment was off just a little bit, turning the adjusting screw 8-9 clicks is a huge adjustment. I think you have shifted everything over 1 cog. It's not a big deal. The most basic adjustment anyone on a bike needs to learn is gears and brakes. Look up some online guides, it does not need a bike shop.
Doing the adjustment was just one of the things I had them do (out of a list of 6-7 things........in prep for my race this weekend). It wasn't just a "little" off. I had to shift 2X to get it to shift 1 gear. It was awful.
I appreciate the corrective criticism. I'll follow your (collective) advice.