Yes, you can. It sure can make it faster, and in that situation I always hope a rocket hog comes along and kills me (we're not allowed to use that tactic ourselves, but we let guests do it if they choose)
It can work on Danger Canyon, Ice Fields, Sidewinder - but the worry is that you waste 10 seconds, then respawn again at the wrong base. On Infinity, you at least know you'll spawn at the right nav. But you may not have a hog to resume racing. If you spawn behind the base, you'll kill 20 seconds walking to score, then have to hunt for a hog. So it's not as guaranteed as you might think. If you stay in your hog, sure it takes longer, but you can be sure of being able to continue racing at full speed. Even if you get killed along the way, you'll respawn at Red anyway.
I think on other maps it's better to walk: you can gun a teammate, or hogjack the enemy, and either is probably better strategy than a 50/50 chance of spawning at the other base, and maybe with no hog.
