Back in the early days of the DIRECTV HD DVR, it was really more of an enthusiast device, more designed for power users than for the average person. There were a lot of hidden features and powerful options that made it easy for people to get past the limitations of that early hardware.
In the 2000s, you could only have 50 Series Links. If you were a heavy TV user at that time, you spent a fair amount of time checking your recordings list, pruning out shows that were on hiatus so you could set up recurring recordings for shows that were coming up. With the Genie DVRs and their ability to store 100 Series Links, that problem went away for the most part.
One innovative workaround built into the DVRs at that time were special keyword search terms. You could always do a keyword search for an actor or category you liked, but by putting in additional nonsense words you could add more function. For example a search for “AANY TREK WARS SEARCH” would let you record Star Trek, Star Wars, and Star Search because each of those had at least one of those words. If you’re curious, I did a whole tutorial on it way back when.
Using fancy made up words made it possible to cram three or four series links into one, especially if they were all on the same channel. It wasn’t very intuitive but it did work.
100 Series Links
At some point the ability to do new searches using those made up words was taken away from the Genie DVRs very quietly. Any searches you’ve done in this way still worked, but you couldn’t do new ones that worked.
The general feeling was that 100 series links was good enough for most people and that if you needed to have more than 100 recurring recordings perhaps the best option would be to be more active in managing your playlist. Very few people really got proficient in using those keywords and they did slow things down for everyone apparently. So it’s a case of “the needs of the many outweigh the needs of the few,” something that makes sense now that DIRECTV DVRs are out there in the millions.