This is forwarded with permission from Trudy Mangels and Charlotte Holtzman.
I think you will find both of their  comments interesting:
Marion
Recently I have been corresponding with a retired breeder who I have long
admired — and as I'm getting to know her, come to consider a friend.
(When I was looking for my current dogs, I traced forward to find lines based
as closely as is now possible to her Brandwyne line — and they have been
everything I had hoped they would be.)

One topic that Trudy and I have been discussing is the sable merle issue
(which she thought had been settled long ago). I have been amazed and
delighted with Trudy's knowledge of the color genes — and especially the merle
gene.

Trudy has received some emails from breeders who are opposed to the
change, making arguments not based on genetics — and the old argument of
protecting the standard. She sent me a copy of her response and has given me
permission to share it with this list — see below. Identification of the
recipients has been removed.

Charlotte Holzman

I cannot believe that this is being so blown out of proportion. I have already voiced my "opinion"…

IF BOTH BROWN EYES ARE PREFERRED, THEN SIMPLY SAY SO, AND LET IT GO AT THAT. STOP MAKING AN ISSUE OUT OF BLUE EYES.

PARTIAL OR ALL BLUE EYES ARE PART AND PARCEL OF THE MERLING EFFECT on melanin….ONE MUST UNDERSTAND THE FUNCTION OF THE GENETICS INVOLVED;

THE CHEMICAL, MELANIN OF THE EYE, SKIN AND HAIR IS ' ALTERED' CHEMICALLY; ESSENTIALLY ACTING AS A DILUENT.

WITH BREEDERS AT LARGE NOT RECOGNIZING THIS FACT IS THE ERROR. NO BREEDER WILL EVER SUCCEED IN PRODUCING 100% or any percentage indeed, of BOTH BROWN EYES IN MERLED SPECIMENS ..WHETHER BLUE OR SABLE …. THAT IS AN INCONTROVERTIBLE FACT.

To keep this simple: THE BROWN MELANIN OF THE EYE, IS COMPLETELY ALTERED TO A GREAT VARIETY OF PENETRATION PATTERNS, SUCH AS UNDISCERNIBLE SMALL FLECKS AND ANY WHERE BEYOND THIS TO THE FULLY BLUE ORB. THIS IS A COMPLETELY NATURAL RESULT
THAT REALLY IS QUITE UNCOMPLICATED TO EXPLAIN. ——

WHAT IS EXHIBITED BY THIS CONTROVERSY IS IGNORANCE, NOT PERFECTION …..SAVVY ?

AND BY …. CASTING MORE SUSPICIONS WITHIN THE BASIC BREED CONFORMATION STANDARD IN THIS, A COMPLETELY NATURAL RESULT, IS UNWISE AND WILL BE UNREWARDING. –

REALLY – A SIMPLY EXPLAINED AREA?…. ,…..

ISN'T IT BAD ENOUGH TODAY WITH BLIND COLLIES AND MALFUNCTIONAL JAW AND TEETH ALIGNMENT? MANY OF YOU CAN STILL RECALL THE TIMES OF SUPER POOR TEMPERAMENT, AS WELL AS POOR MOVEMENT AND DEFORMED HIPS…..

NOW YOU WANT MORE TROUBLE, OF YOUR OWN MAKING!!!?

I KEEP THINKING…. YOU ALL MUST WANT TO COMMIT BREED SUICIDE AND DRIVE MERLES…. ….OUT OF THE MARKET ALTOGETHER!

HAVING A SABLE MERLE CLASS SHOULD BE SUFFICIENT TO TELL THE JUDGE, ANY JUDGE THAT READS WELL, THAT THEY MAY SEE BLUE FLECKS OF VARYING DEGREE AND/ OR EVEN ONE OR BOTH BLUE EYES IN B O T H COLOR VARITIES [BLUE MERLE AND SABLE MERLE AND THAT THEY ARE 'LEGITIMATE' TO THE BREED AND — MOST IMPORTANT OF ALL — NOT DEFECTIVE. ……THIS IS THE NORMAL, NATURAL RESULT AMONGST THE TWO VARITIES. and OF COURSE, in both solid color and white
classes.

******* SPECIAL NOTE REGARDING EYESIGHT: NOT TO BE QUESTIONED UNLESS
THE SPECIMEN ACTS 'BLIND'…. AS ESPECIALLY APPLIED TO DOUBLE-DILUTE
MERLES RESULTING FROM MERLE TO MERLE MATINGS ….. [THESE ARE FULLY KNOWN TO
PRODUCE LIVE GET WITH DISTINCTIVE DEFECTS, THAT OF INCOMPLETE TO TOTAL
HEARING LOSS AND/OR BLINDNESS DUE ONLY TO EXTREME MELANIN DISRUPTION,
RESULTING IN FORMATIVE DISFUNCTION. THIS SPECIAL AREA SHOULD BE FULLY EXPLAINED
TO NEOPHYTE BREEDERS AND FURTHER, THAT THESE GENETIC MALFUNCTIONS OCCUR 100% OF THE TIME. THIS CONSTITUTES A MORAL, PERHAPS ETHICAL, DECISION AND IS UP TO THE INDIVIDUAL BREEDER WHO BREED MERLES TO MERLES….

PERSONALLY, FOLLOWING ONE SUCH MISADVENTURE I HAVE NEVER SANCTIONED MERLE TO MERLE BREEDING AND HAVE ALWAYS ADVISED AGAINST THEM BECAUSE OF THE HIGH RISK INVOLVED….
in CONCLUSION, I would like to repeat that if matched color brown eyes
are preferred, then say so, although I have to add this thought ….. it would
be foolish even here in opting for this, since the marled eye color is just
that – the melanin is always affected and often the blue flecks –
however tiny – are still visible and then you will be encouraging judges to get
out their magnifying glasses to search for them [do you see what can happen
over this ridiculously uniformed, unscientific and severely personally
biased controversy? if blue flecks are allowable
in one or both eyes, THEN SAY SO …or perhaps a note to say that BLUE
FLECKS SMALL AND LARGE, WILL OFTEN APPEAR IN THE PREFERRED BROWN COLOR OF ONE
OR BOTH EYES, WITH NO DEFAULT . Whatever, keep it clear, correctly
explained and to the point.

BY THE BYE….. IN CASE YOU MIGHT THINK TO ASK ME
……..ANY BREEDER THAT DOES NOT RECOGNIZE THE COMPLETE RAMIFICATIONS OF THIS
AREA IS NOT QUALIFIED TO VOTE ON THIS SUBJECT …….SPECIAL GREETINGS TO ALL
! GOD BLESS.