For those following through a news reader, there has been several comments on the article "In search of the truth ..." Two subjects dominate: opinions on Dr Hawass and radar surveys.
I have gone back to Nicholas Reeves' site again and looked at the radar images for Feature 6 (KV63) and Feature 5 (KV64). It's striking that Feature 5 is firstly a stronger/bigger response than KV63 and, unless I am still misreading things, considerably deeper than KV63. Dennis made a useful comment on the In Search of the Truth post when he said.
There is sort of a depth scale in Reeves data. GPR transmitter sends out a single wave at the radar frequency/wavelength. In the case of Reeves 400,000,000 Waves per second (400 MHZ) radar the pulse is 1/(400,000,000) seconds long. As it penetrates rock it is absorbed by the rock and reflected back (being absorbed on the return path as well). A sensitive receiver picks up what is left of the reflected pulse as a function of time. The pulse has a characteristic wave length which establishes the smallest detail which can be seen. For Reeves case this is about 3/4 meters long. Think of it as a vertical pixel size. The banded nature of reeves data shows one band per wave length (about .75meters). Try counting bands on the KV-63 data and comparing it to actual depth of the room. When I first figured out what constituted a band and counted bands I got the actual depth of KV-63 chamber floor.
Personally I still struggle counting the bands (somebody may wish to try) but on simple visual inspection, Feature 5 is considerably deeper than either KV63 or the extent of the excavation so far. For me the only way it could be dismissed if if a new GPR survey has failed to repeat the results, although even then one would wonder whether geology was a factor in it not being visible.