It seems that the 'Naga Viper' that Gerald Fowler is advertising as the world's hottest chile pepper is a three way hybrid cross, being made up of these three peppers: Bhut Jolokia, Naga Morich and Trinidad Scorpion.
All three of these peppers are hot in their own right, so even though this hybrid cross is unstable, it will still no doubt be hot.
Where it will show variability is in size and shape, and though it will be hot, i wouldn't bank on it always being at the 1.3 million scoville heat level.
It wasn't revealed how these peppers were grown or chosen to be tested for that matter.
Until a large scale test such as the one done in 2005 at Las Cruces, New Mexico by Dr. Paul Bosland and colleagues, where they tested and compared Bhut Jolokia, Orange Habanero and Red Savina chile peppers is conducted, the results of a small test for the benefit of a commercial seed vendor, has to be taken with with a grain of salt.
When Dr. Bosland did his testing, he selected from thirty six plants of each strain.
Of these, twenty five random mature pods of each strain were chosen from at least ten different plants of each strain, for HPLC Scoville testing.
It is testing like this, from a reputable source, that will give more consumer confidence for a pepper's expected hotness.
dvg