They are BUT - did you notice the bloating alert?
Second question - have you ever exceeded the 300kcal/hour max with other carbs?
Yes, that's right, undigested CHOs make beer farts. And you're far more likely to have undigested material with potatoes than with gels - because gels are made that way on purpose.
So basically we have a potato puree (read: cold nasty mashies) which, when it's hit by stomach acid, makes exactly the same short-chain CHOs as those gels have, and which also has a high risk of malabsorption with consequent bloating and gas. Why would you? as
@LouD-Truckee points out, there are far better options even if you're staying 'natural'.
On the other hand, every one of the cycling rags publishes "make your own energy bars" and a regular entry therein is - potatoes. I'm all for those in a back pocket. Cut into skin-on-wedges, seethed in bouillon, then baked to golden and wrapped in paper-backed deli foil...YUM and a salt fix too.