Hi there,
There are also problems with soldering SM ic chips too, in that the seal between
the pin and the package sometimes begins to leak because the temperature
profile when soldering isnt matched to the manufacturers recommendations.
This has been a known issue for years now, however many hobbyists solder
these parts too without any special soldering equipment and overall obtain
some pretty good results and the devices dont seem to fail prematurely.
If you are too worried, use two irons of the same type at the same time
to do the two ends of the cap or other part.