No one is suggesting it is not important for the condensor to be clean... that is the bottleneck of any AC system... air across the condensor...
what I am disputing is this :
"" clean evaporator will cool the cabin better...therefore, it will absorb more heat... the evaporator temp will be higher, the freeze switch will not activate, due to the higher amount of heat intake of the evaporator... that heat will cause more stress on the compressor and condenser."" --Vstech

the ' more stress' implies something bad when we are discussing poor longevity from R4 compressors..... but cleanliness everywhere fins are is less stress on the system designed for clean fins everywhere than leaving the fins of the evaporator dirty...

__________________
1980 240d ,

chain elongation, cam marks reference:
http://www.peachparts.com/shopforum/showthread.php?threadid=10414

http://www.peachparts.com/shopforum/diesel-discussion/305365-9-degrees-chain-stretch.html

evap fin cleaning:

http://www.peachparts.com/shopforum/diesel-discussion/156207-photo-step-step-post-showing-w123-evaporator-removal-1983-240d-1982-300td.html?highlight=evaporator

A/C thread

http://www.peachparts.com/shopforum/diesel-discussion/297462-c-recommendations-mb-vehicles.html