Multi-Channel (MCS) Production Tubing was specifically designed for wells that have liquid loading problems.  As gas wells deplete, reservoir pressure declines, and gas velocity up the well decreases.  Even if the gas-liquid ratio entering the wellbore is unchanged, sooner or later, liquid eventually starts to collect in the wellbore because the gas velocity becomes insufficient to carry all of the liquid out of the well.
In a sense, MCS production tubing is a re-invention of the velocity string. They are similar in theory (reducing tubing diameter to regain steady-state flow)… but the effect of an MCS (very small diameter) is to reduce by more than 10 times the minimum velocity of flow needed to evacuate all liquid (i.e., to maintain steady-state production).  This results in greatly extending the timespan of its benefits (maintaining steady-state flow), and by having multiple passageways, fixes the main drawbacks of velocity strings

(restricts production rate and difficulty in kicking off).

An MCS is a new type of “production tubing” that divides the flow up the well into multiple flows through small-diameter internal passageways. By reducing the diameter of each individual flow passageway so much,

it reduces the “Turner Critical Rate” (i.e., minimum gas flowrate/ velocity) required to maintain steady-state flow up the well (see “Turner Critical Rate” page)… and by utilizing multiple flow passageways, it compensates for the restrictive/ choking effects of using a single small-diameter passageway (i.e., velocity string).