db_cooper - you're correct that the LE still appears on the Chevron website but at two Walmarts I checked (one on LI the other in CT) only the SDE is on the shelves. Similarly, you can find a link to LE on the Walmart website, but when you click on it the SDE product comes up. The Costco website also shows only the SDE.
I'll be on a store-by-store search for the LE for now, I may need to change flavors of oil though...

I'm having one of those "everything you know is wrong" moments after perusing the "https://540ratblog.wordpress.com/" report.

Assuming that the purpose of zinc content is to prevent wear in our engines under harsh conditions, then zinc is the means to an end, not the end itself. If your lube of choice has lots of zinc but doesn't protect against wear as well as other oils, isn't the zinc content a secondary consideration? Same applies to synthetic vs. conventional - if a given conventional outperforms an old favorite synthetic, why pay more?

Given that Delo 400 LE seems to be no longer readily available and Valvoline VR-1 is likewise extinct in my neck of the woods, if I were to use this blog as my sole reference, I still can't decide which choices have the balance of protection and viscosity that our cars need. Thoughts??

Another way to look at it and consider from 10,000 ft
.
The BASE in the Oil is what counts and where in the ground it comes from to ME and my OCD management and from working in the oil world at one time too.

Shell = Alaska north slope, good $tuff or they wouldn't be cha$ing it
Brad Penn & Shell = Pennsylvania basin, home of the oil industry in the USA by seniority
Mobil (formerly Standard Oil)= California central valley & coast
Costco/ Wal Mart = West Texas Permian basin
Total = Saudi Arabia anywhere

Oil from Venezuela only works well in Australia, Hmmmm