Accordind to FCTM I understand that I would still have to make those corrections if I were further up North.
When appropriate, make cold temperature altitude corrections by applying a
correction from an approved table to the Waypoint altitude constraints. The FMC obtains the GP angle displayed on the LEGS page from the navigation database. This GP angle is based on the standard atmosphere and is used by the FMC to calculate the VNAV path which is flown using a barometric reference. When OAT is lower than standard, true altitudes are lower than indicated altitudes. Therefore, if cold temperature altitude corrections are not made, the effective GP angle is lower than the value displayed on the LEGS page. When cold temperature altitude corrections are made, VNAV PTH operation and procedure tuning function normally, however, the airplane follows the higher of the glide path angle associated with the approach (if available) or the geometric path defined by the waypoint altitude constraints.
Note: Temperature corrections redefine the glide path only if the FMC has the
geometric path option installed. Reference the applicable FCOM for
optional equipment installation.