According to an aspect of the disclosure, a glass manufacturing system includes a hot-end subsystem, including: a submerged combustion melter that melts feedstock to produce molten glass; a stiller that receives the molten glass from the submerged combustion melter and that includes a stilling tank to still the molten glass and that is configured to control outflow of the stilled molten glass to effectively decouple viscosity of the molten glass from the flow rate of the molten glass and thereby control finer molten glass levels; and a finer that is mechanically decoupled from the stiller, and that receives and fines the stilled molten glass to produce fined molten glass. Many other aspects of the system are also disclosed and claimed.