Reading interventionist teaching full lessons.

At an elementary school where a significant percentage of the students are below level for reading (and mathematics), what are your thoughts on the school having the reading interventionist teach the lessons for small-group skills & whole-group reading for about half a class size of students of a few grades (about two hours each grade, half a class size per grade)? These students would be very below grade level (Tier 3) and at risk of repeating their grade.

If you are a reading interventionist, would you be interested in this or would you feel like that's a bit much to handle? If you are a classroom teacher, do you feel that it'd be beneficial to you? Or any other feelings?