There have been a couple of threads suggesting that HV-charge may behave better (for some set of preferences) than HV, and there have been many complaints related to how aggressively the ICE is revved in HV. Thinking about what it would truly mean to be a "range extender" rather than just a hybrid engine, I have a theory to offer regarding the ICE algorithm in HV-charge and how it could differ from HV. A true range extender would just generate electricity to charge the battery, and not care about the driving conditions. It would likely sit at some highly-efficient load and RPM combination which output somewhat more kW than a long-distance steady cruise is expected to use. In the normal SOC range it would not respond to SOC, and the EV drivetrain would operate the same as it does in EV, even when the kW demand is higher than the ICE output. Contrast this with the goal in HV, which is to maintain SOC. The ICE varies its output frequently to respond to varying driving demands so that SOC does not vary much. This leads to behavior such as high revs even when there is ample battery SOC to drive the vehicle up high grades in EV mode. So, is it possible that, intentionally or not, Honda's engineers have made it where HV-charge keeps a steadier RPM and thus a more pleasant driving experience for those who enjoy quiet, smooth, and powerful EV operation? I haven't taken enough long (and mountainous) trips lately to get direct experience. What are the thoughts of those that *have* driven varying terrain in HV-charge?