This has been a great read, but readily admitting being somewhat simple minded, I just don't see some of the advantages in having peak performance at very high rpm. When I drive, I don't take off from a dead stop @4000 rpm. When at highway speeds, it seems like the gas engines running at that high rpm for long periods of time would have to have a negative toll on them. Yes, they were designed to run at high rpm, but it just seems to me they wouldn't be able to sustain that long term. Please don't misunderstand, I don't mean this to insult the small engine gas fans, I just don't understand.