You make it look so easy...
Your video makes it look like a 15 minute job. I have been messing (the nicer term) with this for 2 hours and I haven't gotten the first cover inserted. I am using Samson fids 5/16" dia. on 5/16" line. After removing the core from the first section of cover, I can't even put the fid through the empty cover, not to mention getting past the crossover. I went down to a 1/4 " dia. fid and I can barely fit that through once I get past the crossover. I am pulling on the core to bunch up the cover. This is off the shelf West Marine double braided line.
I had similar problems doing Eye Splices but I managed to get them done by going up the core 1/3 of the way and then coming out of the cover and then reinserting the fid into the exit hole, going up 1/3 more , etc.
What in the world am I doing wrong?
First,what brand fids are you using? Second, are you using a lubricant on the fid?
I'll check back later, I need to go sailing.