That is not what the last senstance of 110.14(C) says.
Feel free to do it your way but is not required.
I understand it is not required... by convention. The wording itself is neither explicit nor concise enough to say what way it should or shouldn't be done.
...and it wasn't the last sentence of 110.14(C) "general statement" that I am referencing... (see highlighted quote of text below).
General statement does say you cannot exceed the lowest rated temperature.
Subparagraph (1) says to base ampacities on Table 310.16. Is not ambient temperature correction a part of Table 310.16? (a)(2) and (b)(2) do use the word "ampacity" and per Table 310.16 ambient correction is required for conductor ampacity.
110.14(C) Temperature Limitations. The temperature rating associated
with
the ampacity of a conductor shall be selected
and coordinated so as not to exceed the lowest temperature
rating of any connected termination, conductor, or device.
Conductors with temperature ratings higher than specified
for terminations shall be permitted to be used for ampacity
adjustment, correction, or both.
(1) Equipment Provisions. The determination of termination
provisions of equipment shall be based on
110.14(C)(1)(a) or (C)(1)(b). Unless the equipment is listed
and marked otherwise,
conductor ampacities used in determining
equipment termination provisions shall be based on
Table 310.16 as appropriately modified by
310.15(B)(6).
(a) Termination provisions of equipment for circuits
rated 100 amperes or less, or marked for 14 AWG through 1
AWG conductors, shall be used only for one of the following:
(1) Conductors rated 60?C (140?F).
(2) Conductors with higher temperature ratings, provided the
ampacity of such conductors is determined based on the
60?C (140?F) ampacity of the conductor size used.
(3) Conductors with higher temperature ratings if the
equipment is listed and identified for use with such
conductors.
(4) For motors marked with design letters B, C, or D, conductors
having an insulation rating of 75?C (167?F) or
higher shall be permitted to be used, provided the ampacity
of such conductors does not exceed the 75?C
(167?F) ampacity.
(b) Termination provisions of equipment for circuits
rated over 100 amperes, or marked for conductors larger
than 1 AWG, shall be used only for one of the following:
(1) Conductors rated 75?C (167?F)
(2) Conductors with higher temperature ratings, provided
the ampacity of such conductors does not exceed the
75?C (167?F) ampacity of the conductor size used, or
up to their ampacity if the equipment is listed and identified
for use with such conductors
However, one must apply adjustments appropriately. Take for example Norb's situation where most of the run is on the roof but both ends of the run(s) drop down into and are terminated in a 30?C living area. Conventional application of using a higher temperature-rated conductor for termination adjustment would be appropriate.
Yet again, let's say we have a similar scenario but the load end(s) terminate on the roof into 75?C-rated mechanical lugs and the supplied devices, equipment, and such has an equivalent or better temperature rating. The first sentence of 110.14(C) says we must select and coordinate the ampacity so as not to exceed the lowest temperature rating of any connected termination, conductor, or device... which is 75?C in this case. So do we not have to correct for ambient temperature the tabled 75?C ampacity to determine the current level at which the conductor exceeds 75?C?
What if there are more than 3 ccc's in the run? Again the key here is by the first sentence of 110.14(C), we have to determine at what current level does the size used exceed the permitted temperature.
