Lectionary & The Holy Spirit

It seems that most denominations use lectionaries in there services. A lectionary is a sort of schedule of verses to be used on a given Sunday. The churches I attend seem to use three-year lectionaries. I don't think that the lectionary ends up quoting every piece of the Bible, but instead covers the main points.

To the best of my knowledge, neither of the AG churches I attended had any sort of lectionaries for there Bible readings. Certainly we were encouraged to use reading plans - lectionaries in and of themselves - for our personal devotional time, but typically the chosen reading for the worship service wasn't as planned out. I went to two AG churches. The first one's pastor was more methodical, choosing a book and going through it in a structured fashion. The second one's pastor went with what he felt the Holy Spirit leading him to, meaning we might go anywhere in the Bible.

The LCMS uses the Revised Common Lectionary, which was produced in the early 90s. I haven't been involved with Lutheranism long enough to really have a "feel" for it or anything.

There is something inside me that questions the use of a lectionary. Remember, these things pre-plan the Bible verses used for sermons, and may very well be used for decades or centuries, without variation. Does this stop the Holy Spirit from working as he would like? Is it possible that God may intend for a pastor to speak to his congregation about one topic, but because that's not what the lectionary calls for, it doesn't happen? Or is it the case that, in his omniscience and omnipotence, God is able to use the lectionary and get his point across to the believers just by using this structured system? Does God want a lectionary to be used?

Honestly, I feel like God is able and willing to use lectionaries. Mainly because it's what's been done for thousands of years. Jews used lectionaries, as early as the time of Moses according to some. The Catholic church has used them for the entirety of its existence, and even Lutheran churches continue to use it. The way I see it, even if these don't give the Holy Spirit the kind of "free reign" seen in other types of churches, God can still work in peoples' lives through the passages prescribed for a given Sunday.