The lore based ones have already been stated below. The Warlocks, being on a never ending hunt for knowledge, studied the vex and their properties. They had also studied the fallen extensively seeing as they are there on earth aside them. What two things do we know about these two races in specific? Their ability to do a short range teleport, or as we call it, a blink. The warlocks learned the art of blinking on their hunt for knowledge. When they approached the Hunters and the Titans, they demonstrated this new ability. This intrigued the hunter immensely, and the Titan was less than satisfied. He was overjoyed already with the brute strength of the practice of fist of havoc, and the technique behind the Ward of Dawn. The warlocks, who hunted the ahamkara with hunters, we're now practicing this ability during those hunts, and honing it down to perfection. Now let's take a step back for a minute to explain the ahamkara. They were beasts much like dragons, but of unfathomable intelligence. They had the ability to control minds of their victims and sentence them to their death by their own hands. The only thing that could combat these were the warlocks. But these beasts were clever. Hiding, invisible to the naked eye, and waiting to feast upon those brave few who challenged them. That's where hunters come in. Hunters would not only track these beasts, but assist the warlocks in the killing of them. Fast forward awhile. A warlock and a hunter are having a drink after the warlock single handedly killed an ahamkara. The warlock was bragging to the female Hunter while she sharpened her knife. Displeased with her lack of interest, he abruptly screamed at her that she would never be able to kill one of them. Us hunters, being the cocky little killers we are, think we can kill everything. She stood up calmly, faced the warlock, and uttered the words: "watch me". The warlock was scared. He had just sentenced a fellow guardian to her death. But this Hunter was no stranger to the absolute terror these beasts were. She knew she would be unable to challenge one of the adults. She instead found a baby, and slaughtered it. All she brought back to that warlock was its spine (young ahamkara's spine). While these warlocks and hunters were off killing these ahamkara, the Titan sat back, defending the city of twilight gap from the very few fallen that dare challenged its walls. Throughout these adventures, the hunters decided they want to learn the art of blinking. The warlock noticed that the ahamkara had this trick as well, and had more skill in it than the warlocks ever could have though. The ahamkara were using it vertically unlike any vex or fallen they had seen. This is where the warlock started to teach the Hunter blink as they advanced their own techniques. The Titan was never there to learn these tricks and never bothered to be taught them. Therefore the Titan will not have blink as they have never had intention of learning it.