Dynamic Render Distance Adjustment

I was watching Xisuma have problems with lag whenever he moved from chunk to chunk in a heavy lag area, even although the actual chunks he was playing in were low lag.  This gave me an idea.

Dynamic Render Distance.  This could be implemented as a player hot key or as a command block option.  It would have two modes: static and travel.  Say a game is going on in a 10x10 mini-map.  The players would hit their DRD hotkey in the middle of the area and it would lock their render area, so if there render distance is at 12, all chunks in a 12x12 area would stay locked loaded as long as they stayed in that area.  More importantly, nothing beyond that area would load, so no lag spikes. There could be a travel version to, that would be based on speed.  Basically if you are going faster than a certain speed it would dynamically lower your render distance, particularly to peripheral directions.

Both versions require the player to actually be in the area so it's not a chunk loader.  The size should be configurable.  It's not a replacement for spawn areas.  It's about loading fewer chunks for players in high lag areas in a customizable and useful way.