For English, will we be okay using the R and S 4 with a boy who probably couldn't tell me much more than what a noun or verb is? It's not that we've never done grammar, more like he just doesn't care about it

Also, I was reading through the dictation instructions and I wanted to see if I was understanding this correctly. We let the child look it over, then we take it away and they write it out as we say it phrase by phrase, instead of saying the entire paragraph and having them try to remember and write it out?
And lastly, for those of you who have done spelling by dictation only, how has this worked with a poor speller? I'm at a point where we are finally making progress with a spelling program that I really love and I hate to give it up. I'm tempted to do both and drop a few of the Bible activities or hands on projects.
Thank you,
Alison