The Gra on the trup on Vayemararu et Chayeiheim

Summary: There is a famous commentary by the Gra on the trup of Vayigash Elav Yehuda. Here is one on וימררו את חייהם, from parashat Shemot.

Post: I'm always on the lookout for trup related divrei Torah. There is a rather famous one by the Vilna Gaon on the kadma veazla revii zarka munach segol at the start of parshat Vayigash. And I have various "objections" to it, on the basis of the actual names and meanings of the trup symbols. But a big question is just how seriously the Gra meant it. It is often suggested that this was only intended as a cute vort. But looking at other examples where he gives trup-related commentary might help us discover this. That he refers several times to this type of derivation might be indicative that he takes it seriously; his comments on parshat Shemini, reading it into an aggada in the gemara makes it explicit, that he does take this seriously.

Here in parshat Shemot, the Egyptians embittered the lives of the Israelites:

יד  וַיְמָרְרוּ אֶת-חַיֵּיהֶם בַּעֲבֹדָה קָשָׁה, בְּחֹמֶר וּבִלְבֵנִים, וּבְכָל-עֲבֹדָה, בַּשָּׂדֶה--אֵת, כָּל-עֲבֹדָתָם, אֲשֶׁר-עָבְדוּ בָהֶם, בְּפָרֶךְ.

14 And they made their lives bitter with hard service, in mortar and in brick, and in all manner of service in the field; in all their service, wherein they made them serve with rigour.

and the trup on וַיְמָרְרוּ אֶת-חַיֵּיהֶם is a kadma veazla, as you can see in the image above. 

In Kol Eliyahu, the Gra writes:
In the verse vayemararu et chayeihem baavodah kasha, etc., behold the melody of the words "vayemararu et chayeihem" are kadma veAzla. There is to say that it comes to hint to that which Chazal said, "Why was Israel in Egypt only 210 years -- behold the decree was for 400 years! Rather, because of the difficulty of the sevitude it completed the time." And this is what the kadma veAzla is hinting at -- that is to say, that they preempted (קדמו) and left (אזלו) before the established time, via the vayemararu et chayeihem in the difficulty of the servitude, via that, that preempted to go before the time, and this is kadma veAzla mimitzrayim.

Of course, if trup is mechanical, automatically produced by rules having to do with the syntax, then this sort of deliberateness in trup is less likely. As it would be if the names of the various trup markings were originally different.

But subscribing to this theory, I think that I can extend his interpretation of the trup a bit further. After all, the trup on baavodah kasha is munach revia. If so, we can say that they preempted and left, from the staying put (munach) of the four hundred years (revii).

Other than that, I have no other comment. I am tempted to cover the other instances of the Gra interpreting trup that I can find, even though they are outside of parashat Shemot.