Frequency is nothing new. Nearly everyone on Tnation has dabbled with high frequency training. It’s fine for short bursts/peaks. The problem with it is most do too much daily volume, and pain/overuse/injury chance is elevated. It’s not a good way to build a long term training plan. Now, it can be a block or a piece of a plan, but not the whole plan.
However, people like @ActivitiesGuy have found a high frequency low volume approach that he progresses with and enjoys.
As far as full body goes, I absolutely subscribe. Training the entire body each session resonates with me. It just makes sense. I feel like I can keep everything optimized. Frequency, intensity and volume. So I train 3 hard full body sessions per week, with 2 main lifts per session that get trained hard and are the ‘focus’. Then I bodybuild the assistance work.
Everyone’s going to do it a bit different. HOWEVER, it’s good to have more tools in the toolbox then less!