Muir,
the 'detonation' phenomenon is almost entirely confined to large magnum size and other very 'over bore capacity' cartridge designs using powders that are very much slower burning than 4350, and has rarely if ever been induced under laboratory conditions. When it was first reported, the late B E Hodgdon, founder of the Kansas powder company, had great doubts about its existence and tried repeatedly and unsuccessfully to make it happen in the laboratory. He was of the opinion that while it might happen under vary rare conditions, most so-called detonation incidents were due to something else, such as an incorrect powder being used by mistake. It's happened often enough for most people in the industry to now accept that it is a possibility, albeit a very rare one. The exact mechanism has never been determined - the most common theory is that it involves the creation of a pressure wave in the case allied to the powder charge being slammed into the front end of the case in a solid compressed block of nitrocellulose.
I would have few worries about seeing detonation in .30-06 with any of the 4350s even if only half to two-thirds standard charge weights were used. What you will inevitably get are large pressure variations and poor results due to the powder burning at inadequate and inefficient pressures. Detonation aside, use of a correct burning rate powder in sensible charge weights is a very GOOD IDEA. Some loading manuals print starting loads that are way too low in my opinion, down 15% or more on what are often modest maximum levels while Hodgdon traditionally advises users to start 6% below maximum, and 3% down with certain (usually ball) powders that need a maximum or near maximum charge to operate properly.