I´ve not read the other posts but there is absolutely no need to harmonize the four Gospels. If I gave four men or women, each, a camera and assigned then the same subject they would come back with four different perspectives of the subject. And if I assigned four reporters to observe the same event, when they submitted their articles their would be four different perspectives of the same event.The harmonic problems have concerned christians since the four Gospels were circulating. The first attempt of wich we have news was the Diathessaron wich not only failed to provide a solution but included several apocrifa. The Diathessaron quikly subtitued the four Gospels in popularity, but - thamks God - it was prohibited and burned.
Agustine is the next to do an effort to fix the harmonic problems, but his work resulted insuficient.
We have no news of any other attempt to solve the harmonic problem; not until the XX Century. Is then the last years wich produced more works pproposing different solutions, but no one claiming to be satisfactory, but recognicing the obstacles that couldent be superated.
How important can be a final harmony, providing a satisfactory solution for all the harmonic problems?
In court we know people are lying when their stories are, very much, the same, they planned what they would say. The differences in the four renderings of Christ´s ministry lend to authenticate then as being true.
I pray this helps and may God bless!