Come now, Keble, you don't expect me to go for this, now, do you? I think you are fully aware of the importance of Holy Tradition in Orthodox ecclesiology. You must also be aware of how we cringe at using words like "acrretion" or "innovation" to describe changes made to the liturgy. Such terminlogy effectively implies that the Holy Spirit had nothing to do with any changes made. Of course, many things were added to the liturgy, at least in part because of human expediency. This does not exclude the involvement of the Holy Spirit. We Orthodox believe that God and humanity work together in synergy in the Church.
This is true, but it is my observation that the more traditionally minded online Orthodox seem to place more emphasis on God's influence on the Liturgy than that of man. Synergy works both ways. This is not to say that we can do whatever we want with the Liturgy, but only that we need to keep both factors in mind.