One grub, two operating systems, problem solved.

[Chuck Hallenbeck]

Hi John,

I made no other changes to either system other than a couple of items in the
default grub file, but those things weren't obviously related to my issue either.
Examining the generated grub.cfg file,
I noticed that the default kernel command line used the quiet parameter,
but the secondary kernel command line did not.
I was unable to figure out where to add a quiet parameter to the secondary
kernel command line, so ended up exploring the effect of configuration changes.

The Arch wiki also describes adding an extended tune, which I tried but didn't like. 
Maybe because I didn't recognize the tune. I may take a look at your package.

The nearest I can make out as the likeliest change relates to my disk partitioning scheme.
Although the system is uefi capable, I used the MSDos  scheme. The grub configuration by default pre-loads modules for both
schemes. I removed the part_gpt reference,  and the booting
went much faster once I made the menu selection,
and both installations began speaking only at the login prompt.

So really, it appears to have gone away, but I can't say I know why.

Chuck


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