That is not true in and of itself. UHF has a shorter wavelength than VHF, which affects how it propogates. However that by itself does not directly cause it to have greater, or less, range.
There are a great many things that can affect range of a radio/tv signal, which I am sure relate to Earl's specific experience. But someone else, someplace else, could very well have just the opposite experience.
OK...here's a quick and dirty primer for ya:
1. Path loss is proportional (logrithmically) to frequency. As you go up in frequency, path loss goes up with it. However, lower frequency VHF is power restricted by the FCC, so VHF channels 2,3,4,5 all have very significant power restrictions...and they have lower gain antennas (both at the transmitter and at your receiver) So what they gain in lower path loss, they lose in power restrictions and antenna gain.
2. Vegetation loss goes up with frequency, and become troublesome at 220 mhz and above, becoming near brick wall at 2 gigs
3. Noise immunity improves with increasing frequency.
4. Signal enhancement due to tropospheric ducting improves with frequency, up to at least 1200 megahertz.
5. Signal diffraction improves with frequency (big help to those in valleys)
For the same size antenna, gain and directionality of a properly designed antenna will be substantially in favor of UHF. This along with #3 above improves the signal to noise ratio of UHF stations. This is true of both the transmitting and receiving antenna, not to mention the vastly increased authorized (and used in our area) transmitting power on UHF.
The only issue with pointing is if you have your HD OTA transmitters located in places that are greater than about 20 degrees apart in azimuth from your location. If the transmitters are in the same location, go for the biggest UHF antenna you think will stay up (very big grin). Chances are very good that your UHF setup will equal or outperform a VHF setup, and especially if any of the channels you are needing are in the Channel 2-5 range.