No, and yes.
E.G you could do the level 0-400. but level 0-100 be equal to level 0-10, and 0-200 be 0-20 and so on. This would still be a HR, even though "advancement" is the same speed but spread-out over more numbers.
Once you start with a LR, and say increase the range from 40-70 the natural thing to do, would be to also make the level 0-40 lot easier to do, when you've done this a few times, e.g moved to 100-150, also the DC/SC/MC/AC/AMC gets a lot higher exponentially as you go through the levels, so it essentially becomes a HR, or you have a server which slowly dies as no-one will want to grind 0-120 for 4 and half years, just to catch up. (or you increase the start level).... There is no real difference between a HR/LR except the size of the numbers basically...
The reason its called a HR, is because the numbers are a lot larger giving the impression of faster advancement, when really nothing has changed and everything is quantifiable,
The majority of the uneducated fools who patrol these forums how-ever, don't understand that. they make a direct correlation with large numbers and easy advancement massive weapons that take up 3/4 of your screen and glowing orange skulls for armors., therefor will not play a server with large numbers.
Meaning this server team will be stuck in limbo once the content has run out for 40-50, as the cry baby's will want to keep it "Low-rate".
Low-rate means low numbers, HR means High numbers, that's all it is. I see it as my personal issue to educate the masses on this as i strongly believe MR/HR are the only way to go, and we need to get rid of the stereotype every one has stuck in their heads. Otherwise we'll just end up with cycles of LR's starting and closing down. A HR Can still be balance, and can still have that "euro" economy and advancement, just over a larger range of numbers.
An example of this would be FH HR, which was a HR (lvl 0-400) but items were hard to come by, and the gold and advancement was balanced you couldn't do lvl 0-400 in a day...would still take you about 1-2 weeks, (which is what it took to do 0-40 on euro). How-ever most of the people playing Chronicles would of not even tried FH because of the "HR" tag.