The consensus on the mailing list seems to be that this is not the place for (historical) gikun unless they pass some kind of objective criterion, e.g., inclusion in a major dictionary.  As pointed out, Google usually overestimates the number of hits in any case.

Rejecting the proposed changes.

I have joined the JMdict/Edict Yahoo group as you have 
suggested. Should I just start a conversation there on 
this topic? Before I do so, I just want to make sure you 
are aware that 文語訳(明治訳)舊約聖書 is a regularly quoted 
from version of this early Japanese translation of The 
Bible. As you probably know The Bible is one of the most 
quoted from pieces of literature and this translation is 
no exception. You should literally be getting hundreds of 
google hits when searching for the gikun I am proposing. 
The reason you are not has to do with how you are 
searching. For example, when you searched for 曠空い 
(proposed on another branch) you must have searched as 
"曠空い" when you should have searched "曠空(むなし)" or 
even "曠空(むな)" which will generate hundreds of matches. 
I would not include the い ending because that may be 
changed depending upon how the word is used. When you 
search for a gikun reading like the one I am proposing 
here, you should search "淵(わだ)". Doing your search 
this way, you will find that there are over 300 pages in 
your search results. That is because when uncommon gikun 
is used, the kana will be shown in parentheses after the 
kanji in most cases (unless rubi is utilized). Feel free 
to respond to this here, or I'll move the conversation to 
the yahoo JMDict/Edict group conversation board.

restoring proposed change. however, i do not approve of it without further evidence that this is not just an idiosyncratic choice of a single translator

@@ -22,0 +23,5 @@
+<r_ele>
+<reb>わだ</reb>
+<re_inf>&gikun;</re_inf>
+<re_inf>&ok;</re_inf>
+</r_ele>
@@ -24,0 +30,3 @@
+<xref type="see" seq="1201190">海・わだ</xref>
+<xref type="see" seq="1201190">海・わだ</xref>
+<xref type="see" seq="1201190">海・わだ</xref>
@@ -25,0 +34 @@
+<s_inf>わだ, referring to the sea (the deep), is an obsolete gikun reading for 淵 found in Meiji period literature</s_inf>

in my opinion, a single source is not adequate evidence for the addition of the alleged gikun

please discuss the addition of these gikun readings on the mailing list
https://groups.yahoo.com/neo/groups/edict-jmdict/info
===
i am temporarily rejecting this amendment to approve a change in xref type (瀬 is not really an antonym)

@@ -23,5 +22,0 @@
-<r_ele>
-<reb>わだ</reb>
-<re_inf>&gikun;</re_inf>
-<re_inf>&ok;</re_inf>
-</r_ele>
@@ -30,6 +25 @@
-<xref type="see" seq="1201190">海・わだ・1</xref>
-<xref type="see" seq="1201190">海・わだ</xref>
-<xref type="see" seq="1201190">海・わだ</xref>
-<xref type="see" seq="1201190">海・わだ</xref>
-<xref type="ant" seq="1374360">瀬・1</xref>
-<s_inf>わだ, referring to the sea (the deep), is an obsolete gikun reading for 淵 found in Meiji period literature</s_inf>
+<xref type="see" seq="1374360">瀬・1</xref>

@@ -29,0 +30 @@
+<xref type="see" seq="1201190">海・わだ・1</xref>
@@ -32 +32,0 @@
-<xref type="see" seq="1201190">海・わだ・1</xref>
@@ -34 +34 @@
-<s_inf>わだ referring to the sea (the deep) is an obsolete gikun reading for 淵 found in Meiji period literature</s_inf>
+<s_inf>わだ, referring to the sea (the deep), is an obsolete gikun reading for 淵 found in Meiji period literature</s_inf>