The correct answer is - it depends...
On less steep grades, you can often coast in neutral the whole time. On steeper grades, I usually use ECO regen and put it into B mode only if I'm still picking up too much speed.
So, there aren't really any golden rules to lean on for all circumstances, it's a bit of an art and there's definitely a learning curve but it's worth the effort on longer trips.
Vancouver, CA owner of a 2013 Ocean Blue SV + QC, purchased 01/2017 in WA
Zencar 12/20/24/30A L1/L2 portable EVSE
1-1/4" Curt #11396 hitch
After market, DIY LED DRLs
LeafSpy Pro + Konnwei KW902 ELM327 BT OBDII dongle
Loving my first BEV