According to the docs, "When adding products to opportunities, quotes, orders, or invoices, at times, salespeople need to specify the product prices ad hoc." I don't find this to be so; I have not examined the case where the privilege to override price is extended only the one where "use default" is set.
Given an opportunity having NO price list assigned for an account having no defaultpricelevelid, I added an opportunity product. It gets a price. I tracked this down to the default price list of the product. Note that the price list item amount is a required field and that the item's default price list is a required field. Hence, it is not possible to bypass the use of the "default".
I went a little farther and changed the default pxLst on the product to a list of which it was not a member. Surprisingly, the app allows one to do this without automatically creating a price list item. In this configuration when the part is tried as an opportunity product, an error occurs -- this part cannot be added because it is not on the opportunity's price list. The message is probably just not upgraded as this wave 2 feature is that the opportunity price list is OPTIONAL.
Either take this a bit of investigation under the hood or as a question about what more you have discovered about this behavior -- or how one can configure things to do more complicated price automation without code.
ps- my next issue is going to be applying a custom view to the product line lookup. Hope the new feature provides more freedom than previous product line functionality.
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