I didn't see anyone mention Travis Wurtz. I'm not sure if he has any just about grinding but his take can be really enlightening.
My advice for plunge grinding (I'm still new and don't always get it right but sometimes another new person has the same problems and is familiar with the path needed.) Is to try to take as many variables out as possible. A file guide can really help. The next thing is the tool rest. It's in the way for a lot of tasks but when doing the plunge you can line them up and the rest will control one angle. If you watch one of Travis Wuertz videos he often is using a rest for hogging. It's not just a LOT fast but its more accurate. I often cut a tiny angle on my push stick and it helps set my bevels. You have a nice big flat spot afterwards for starting your finish grinding. One last tip that lots of people have posted but I just started using is to wait until the end for the last bit with the plunges. Leave extra material in the area and bring the grinds down with finer grit than what you hoped with.
My advice for plunge grinding (I'm still new and don't always get it right but sometimes another new person has the same problems and is familiar with the path needed.) Is to try to take as many variables out as possible. A file guide can really help. The next thing is the tool rest. It's in the way for a lot of tasks but when doing the plunge you can line them up and the rest will control one angle. If you watch one of Travis Wuertz videos he often is using a rest for hogging. It's not just a LOT fast but its more accurate. I often cut a tiny angle on my push stick and it helps set my bevels. You have a nice big flat spot afterwards for starting your finish grinding. One last tip that lots of people have posted but I just started using is to wait until the end for the last bit with the plunges. Leave extra material in the area and bring the grinds down with finer grit than what you hoped with.