The closest I've been to this situation was pushing baby hardlines, but I think that's a similar enough comparison. No way in hell could someone new could be fast at pushing baby hardlines. Baby food, it's all orange and green, finding the right orange baby food among the 10+ per brand is a challenge. Toiletries, also super detailed, you don't think about it when you know it, but it's confusing as hell. Box of wipe warmers, on the opposite end of baby hardlines than the wipes. Where are the outlet covers hiding? Several UPCs/design differences are covered under one dpci in sippy cups and pacifier clips, not each barcode/design having its own peg. The one I never figured out, why does the shelf count not work with the diaper genies?
I gave new folks a tour of baby hardlines and they still were really slow at first. It's to be expected when you know nothing about the layout of the shelves.