I understand what you mean to say. But honestly I disagree. In charge sustaining mode the net effect is zero on the battery, yes. But that’s net. When going uphill the battery is drawing down, and when going downhill the battery is getting charged back up. But the battery is always contributing on every uphill. And therefore there is more than 103 hp available during those uphills. The battery will catch up on the next flat or downhill or even during more gentle uphills by spinning the engine at faster rpm. I firmly believe, and have felt, that 181 hp available on every uphill regardless of steepness or duration. Because on the downhill it might be expending only 20 hp or even zero hp and adding regen back into the battery while the engine is still spinning at high rpm assisting on the catchup phase.
For example we reached the top of a 12,400 ft pass last fall and pulled over to an overlook for photo shoot...just 2 adults but back seat and trunk had hundreds of pounds of luggage and food for a 3 week trek. As I brought the car to a stop the battery gauge showed one bar, the car was at a dead stop, and the engine was spinning not full throttle like earlier in the run but still fast...like 3000 rpm I would guess? It was essentially in a self induced charge mode catching the battery back up to 2 bars where we had started the climb. But it had enough gonads even with low battery to make that climb just fine, albeit engine was likely spinning 5000 rpm most of the way.
Your explanation implies you only have 103 hp to get up long mountain grades. In my multiple experiences driving up long passes, and sometimes flooring it to pass slower vehicles that are struggling to make the top, it feels as though it has more than 103 hp on tap every time, whether battery is full or at two bars. Obviously I don’t carry a dyno and can’t quantify this. But I’ve driven some of these passes in NA 4 cylinder cars before that legitimately have 100 to 120 hp and are much lighter than Clarity, and some have struggled to even maintain 60 mph with foot flat to the floor. Clarity has a notable bit extra to spare, and is heavier. It feels like a 181 hp 4000 lb car should
In those circumstances. If only engine power was available, understand it is mathematically reduced to about 66 hp at 12k feet in non turbo applications. see
http://www.wallaceracing.com/braking-hp.php )
If only 66 hp was available to move the car at 12k ft, a 4,000 lb car could NEVER maintain highway speeds, much less accelerate while climbing. Yet it does with engine fully uncoupled from wheels. The only possible explanation is because the battery is providing propulsion in addition to the screaming generator engine, and it has enough reserve to do so even with 1 bar showing on the battery gauge.