Most of us do NOT have horses that ride bridle-less or close to it, so we ALL end up "choking up" for control when we ride, and I often change the length of my reins every time I ride every horse. Here is "Corporal" (1982-2009, RIP) in 2007, at 25yo.
I have slack reins bc we're halted, but even THEN, if we were to take off I would have to shorten my reins. He LOVED to race!
I'm not a fan of split reins bc you get caught up in making sure that they are even and, IMO, you stop paying attention to your horse. I prefer, with my Western bridles, to hang and evenly knot the ends of my reins. Then I KNOW that they are even, and the knot gives me something for my other hand to grab when I choke up. THESE reins are period type and sewn or buckled together, like English reins.
I think it's a skill to walk your hands up the reins, but that's my opinion. Do it if you wish, but I use both hands to adjust length.