Yes, it is a little bit vague. It's intentionally vague. The abuse of LI is designed to be like porn: I'll know it when I see it. It's totally fine for it to b

Yes, it is a little bit vague. It's intentionally vague. The abuse of LI is designed to be like porn: I'll know it when I see it. It's totally fine for it to be vague. I very much doubt we'll see any cases where the general public disagrees with a DPA ruling of LI applicability. As a business owner, it means you need to strongly justify it and consider if a "reasonable person" would consider your use of LI to be justified. If you have doubt, you should seek consent instead. Do keep in mind, that growing your business by using PD for marketing purposes is explicitly excepted from LI.