Ita.
Not only was Barbara on a clear trail, it was bordered closely by thick Cholla cactus growth.
Even if she felt dizzy-- the pain of those cacti would've kept her from wandering very far.
Per the photos by sroad and others; which has been so helpful in understanding what a clearly marked path Barbara was on.
And we still don't know if she was actually drinking beer or even if she had a beer container in her hand.
There's never been any proof that she was drinking.
Possibly a drone search could help if any clues can be found that lead to where Barbara actually IS.
Keeping up hope for her nephew, son, and siblings.
They loved her so much !
Her "clear trail" intersected with at least one other, where she had two equally passable options (that's taking the most optimistic view of where RT and BT separated). We do not know which trail she was on. The search clearly moved along 2 different trails. But there are some other trails (if she made a mistake at the intersection). Eventually, both of the main trails hit the road, but at two different places (one with the RV, one without).
I view statements by witnesses as evidence. A good drone search would certainly help. The area on the other side of Kelbaker (where presumably, she was headed in any scenario) is huge, it isn't bounded by cholla or by big rocks, and there's actually a road with several more trails/places to walk.
If Barbara, already more compromised than either of them realize (and perhaps, RT is too - like those people in Zuma Canyon this year) starts off walking fast (I wish we knew her speed), I often ponder how far she'd get before she realized she was on the wrong trail. If she were fully functioning, mentally, she'd notice that she was parallel to the road within 10 minutes (at least one car would come by, I'd think). She should already be at the RV.
What does she do then? What if she's now a bit distressed? Or a lot distressed?
Does she retrace her steps (and does she remember not to take tiny trails/traces until she gets to that bigger intersection)? Does she look for a suitable place (without sharp things) to use for toileting? Does she decide to cut over to the road and walk along it? Does she not get lost at all, but makes it to the RV and can't get inside? Does she then walk down Hidden Hills (lots of discreet places to go behind a bush and not so many prickles). Virtually no traffic on Hidden Hills.
A person can get themselves a little lost in 15 minutes; a lot lost in just a bit more. But, if Barb had been hydrated and healthy even after 2 hours of hiking in 100° heat...she'd have heard the traffic on Kelbaker road and gone toward it. She would have been able to see the road from the Granite Hills Side, perhaps not so much from the Kelbaker side.
So I keep pondering whether she really might have collapsed. The Zuma man was from a very warm area in SoCal but collapsed while in 90-95° heat, on a hike with 5 other people. Just this last summer, after Barbara disappeared. He was perceived by his companions as fine one minute (but two of them would collapse before making it to the trailhead, IIRC). He was 65 years old (maybe a bit younger, I'll try to check) and considered healthy and fit.
He died before they could get help to him.
If she did collapse, it was not within the main area of trail(s) near the Granite Mountains.
People think they're drinking enough water, but aren't, etc. But where is she? Drones definitely would help on the Kelbaker side at this point (and also just north of the creek bed where RT apparently went to take photos).