I have never heard of or had a cable "swell" internally, and I always use a little Tri-Flow or something. Never had a problem. If the whole thing is tight after a short time, I'd think maybe the grease is too thick or somehow it attracted enough fine dust and formed a paste. Sounds to me like you used some pretty thick grease. (Really, did you think a bike cable generated the same heat as a car's wheel bearing?) Maybe just too much grease collected too much dust.

I wouldn't "smear" grease all along the length of a cable ... too much area to attract and bind dust. I use a couple drops down the housing before I run the cable. Has worked on commuter bikes ridden in heavy rain day after day, on mountain bikes ridden in every kind of foul condition, touring bikes used for days on end in all weather ...

I have never heard of grease making the inside of a lined cable swell ... but maybe you are the first to discover this. However, so far that hypothesis is unproven. Did you try cutting open the cable at various points to look for signs of swelling?

You might have discovered something we would all like to know.