Well your man at the saw mill doesnt know his stuff then.
Turkey was first thought to be the answer to the UK oak need for the navy- fast, straight growing oak. Unfortunately it was soon found to have no structural strength, massive movement in drying, and was very susceptible to decay out of doors. It became known as Wainscote oak, as the panelling in old houses (wainscoting) could be made out of it. It also used to be prized by furniture makers, because if you successfully dry it without too much movement and splitting, it is a VERY attractive timber, the medullary rays being particularly wide and strong, and present in alot of the boads from the log, even when live- sawn not quater sawn. I have twio cabinet makers who regularly ask me for it.
Like most things in the modern world, this knowledge has largely been lost, and turkey oak has a terrible reputation.
A sfar as burning it goes, it isnt a bad burning wood at all. It has a fairly high calorific value, as does most oak, hence its quality as a firewood, but it will need more drying to get the same M.C as (for example) pedunculate oak. It also has a very wide band of 'sapwood', which will rot fairly easily, so I have found that splitting and drying under cover or in a very windy place is necesary to avoid loss. It splits okay too.