http://www.burntorangenation.com/2017/2/27/14753708/isaiah-taylor-houston-rockets-deal-rio-grande-valley-vipers not guaranteed...but a step in the right direction.
This is the 4th time he's been recalled then he goes right back to D. I'm guessing they're getting him into practices and team functions periodically. I wonder how common that is?
I don't know how common it is, but the Rockets actively use their D-league roster moving people up and down, at least they have in the past. They did it with Clint Capela (sp?) before he was a regular.