The big difference between Zwift drafting and real drafting is that you don't feel the effect. It is up to you to back off a bit when you get into the draft. IRL, you'll feel the wind resistance change. If suddenly your trainer was signaled that you are in a draft and went easier it would just feel a bit more natural. Instead all Zwift does is move you up or down the drops to show you in the draft. My goal isn't speed but power though so drafting would actually work against my goal. If I can power myself up to draft an individual I'm more likely to want to just power past them which is what Zwift will do. Of course riding a pack is different as the effect is much greater. The big problem I have in the robopacks is backing off to match their pace, I'm always jumping in front.
And .1 is 10%, .2 is 20%, which is what I said. I just didn't remember which went with uphill or downhill.