I believe a clogged pen can be unclogged by putting the nib assembly in an ultrasonic cleaner with non-sudsy ammonia for extended periods of time; several days maybe. Often works.
And this contribution, circa 1972, from an OTR driver from Norcross, GA whose drawl was so thick I could barely understand him. (I'll just cut to the punchline):
2nd woman: 'Better tell your man that drinking all that Coca-Cola will dry the ink in his pen.'
1st woman: 'That's OK, he doesn't do all of my writing anyway.'