Hey Jace,
We will be switching to a similar model soon. We received the same pushback, but it was alleviated when we told them that any Lead that Sales generates will go straight to them. Then, any Lead that we generate will be Nurtured but we will keep the threshold minimal until we gain a better understanding of how Leads interact with our website, WPs, trials, etc.
One key point to make to Sales is that not every name you acquire is a true Lead. In order to pass them interested parties, nurturing and some top-funnel qualifying is necessary. But, this all depends on the amount of Leads that are being created as a whole. I would also go back and look for Leads that have been generated in the past 3-6 months with no activities associated and still sit in Open (or whatever your equivalent is) Lead Status. If there is a large number, you can use that in your discussion to show that there is too much information and Leads are being overlooked/forgotten.
But don't worry, this discussion is pretty universal and you are not alone!