Of all the guys leaving early, I think he stood the most to gain by coming back. He still looks pretty raw as a receiver and while he can learn in the NFL and get paid a year earlier, I think back to an economics class in college. On the first day, the instructor showed a chart of someone going into the work force (and finding a good paying job for the circumstances) right out of high school vs someone getting a degree and then getting a good job.
It's no surprise that the HS person makes more and has more even after a few years of what would be college graduation, but the college person will eventually have more earning power. I think that's where coming back for another of eligibility comes into play for football. For some guys, returning isn't going to improve their draft stock much, but for others, it could mean a couple of rounds earlier. In the end, waiting another year might actually net you more money even if you never make it past your rookie contract. I think that's where Jalin might be.
However, Jalin has his reasons and it's been fun seeing him grow over the past two seasons. On punt returns, he's went from, "Oh, crap please catch it!" to, "Alright, let's get a BIG return!"