It's not uncommon to open a old AEP with stuff in the EGP. Then, it's even more common to forget WTF a property is, in the EGP. Or at times, you may receive an AEP with stuff in the EGP and an alien with little to no human contact had worked on the EGP - I'm sure this has happened! I googled and received tons of results!
So, for the love of HAIR , sanity and Thick, Juicy Burgers. it will be really, really, really useful to be able to select a prop in the Timeline and have the option for Reveal In EGP.
Motion Graphics Brand Guidelines & Motion Graphics Responsive Design Toolkits