Great videos. You've got some skill here. This is the kinda stuff that will make me a better knifemaker. Kinda off-topic here, but I'm noticing also that you use the "pinch grip" exclusively. I like it too for the little bit of cooking I do. So, do you think you would hold the knife different if the handle had more texture or was a different shape?
About pinch gripping, I got taught in a chinese kitchen to exclusively pinch grip my chinese chef's knife. According to the chefs, extending your finger over the spine is a big no no. I personally think its much to do with the handle. The chinese knives that are available here all have round, wooden handles. this makes it more difficult to control the blade to prevent it from slipping left and right. With my yo- handled knives, I switch between the pinch grip, with my finger over the spine and a hammer grip depending on what I'm doing.
I use some form of pinch grip almost anytime I'm cutting. In general, I find the bulges in nice western handles to often be either useless or minor inconveniences since they end up at my shortest fingers. The one major exception is for slicing boneless meat where I might use a hammer or finger-on-the-spine grip.