I read your article of “Deai” with an interest.

Although you might have already gotten the difference:
Defenitions from a dictionary appear simple.
“出会い” is used to describe an opportunity where 2 or more persons meet, whears “出合い” is used when 2 or more objects meet or join together. For example, when a tributary meets a main stream of a river, the place where they meet is described as “Deai” of those rivers. They sound simple, don’t they? However, to my perception, it contains so much meaning, because the song at Houzouji is written for any object that exists in this world but it is a message to us all.

We are here as human being, yet we are, simultaneously, something that is part of the nature. If we define ourselves as just an object which is no more different than the other substances/objects found in this current world, using “出合い” to wish for good encounters would be more suitable than using “出会い”.

Also, my wild guess goes to the point that the “出合い” may be indicating the fact that we are not in the control of which Go En “ご縁” to meet. Go En is something provided. Thus, “出合い” rather than “出会い” insuniates the idea that our life is not driven by ourselves but by someone/something else…

…I may be making the thing so complicated… but as a remark, “Everything will go smooth if you do not stick to it”, that I heard during the talk session conducted by one of the buddist monks last year was reminded while I was thinking of the difference…

Thanks for an inspiring observation.

by “Almost Too Simple To Pronounce”