There seems to be some confusion when it comes to the difference between linear progression and linear periodization. Perhaps this is me just being pedantic but this is how I see the two:
Linear progression refers to the routine adding of weight to the bar on some sort of repeating interval (daily, weekly, monthly). This happens a lot in beginner programs like starting strength, 5×5, etc.
Linear Periodization is a planned linear inverse relationship between volume and intensity. For instance, at the beginning of a macrocycle you start out doing sets of 8 and near the end you’re doing singles. The weight has gone up and the volume has gone down.
Clearly these two concepts are not mutually exclusive. With linear periodization you will probably have some sort of linear progression. Intensity is going to go up ergo weight goes on the bar. However, linear progression does not imply linear periodization. If you linearly progress a 5×5 program you’re adding weight to a topset or sets across, therefore intensity AND volume are increasing.