After a little trial and error, I have found the magic combination of settings to allow Tether to work on the Thunderbolt.
**NOTE**:
The settings below assume you have used Tether before, and know the location of the listed setting on your laptop/netbook & HTC Thunderbolt. Please ensure you have installed Tether in both location First.
Hardware:
** Asus Eee PC 1201N
- Windows 7
** VZW HTC Thunderbolt (Stock, NOT Rooted)
- Android ver. - 2.2.1
- Kernel ver. - 2.6.32.21...
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Laptop/Netbook Settings:
- Turn off Wireless Network Card (Bluetooth may be enabled)
- Run Tether program
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HTC Thunderbolt Settings:
- Enable "USB debugging"
- Set USB Connection to "Charge Only", when connecting to PC
- Run tether program



I agree with the above procedure. With 2 bars of 4G showing on my Thunderbolt, I get 15ms Ping, 10Mbps download and 2.25Mbps upload. While not as fast as I get if I run the Android Speedtest app on my phone, these laptop speeds are more than acceptable.
I used Tether on my Blackberry Tour with 3G for 18 months and found it to be very reliable, if a little slow (200ms/0.7Mbps/0.25Mps). I do highly recommend Tether for "away from home" use.