If you're not aiming for VLC, it's not a huge problem. Coconut juice is great pwo because it contains natural electrolytes, and the sweet potato is one of the better high-carb foods out there. I wouldn't do this every day, but it's not bad in and of itself.

Not a problem per se, but it really depends on your goals and your current body composition. If you're obese/overweight and trying to lose weight, I'd stick to just one (or none at all) and keep yourself lower carb to nudge your body towards burning body fat. However, if you're average weight/at goal/or an athlete (by my definition an athlete is just someone who works out a lot), then your body would actually benefit from both sources to refuel the depleted glycogen in preparation for your next workout.

I though tmost coconut juices were high in sugar. Check the ingredients. Pwo carbs should come from the sweet potato. The coconut juice if no sugar will be pretty much all fat. Which is ok. Just a little heavy post workout