>without an individual subscriber receiving too many deals. Correct. 1 refers to the rate per individual inbox that was entirely essential for their initial gr

>without an individual subscriber receiving too many deals. Correct. 1 refers to the rate per individual inbox that was entirely essential for their initial growth and traction. Total volume and market segmentation > 1 ... is a no brainer for any business. While they can now afford to alienate and loose businessmen and others with low inbox noise tolerance, limiting the bandwidth they consume in each individual's inbox is still their weakest link and one of the only ways for them to actually loose subscribers.