wanting some advice if possible .

checking hypothetical pedigrees of pups that may be produced and have noticed that stud dog and bitch have the same great grandfather . this is showing at great great grandparent level on a 5 generation pedigree .
giving all health tests etc have been done and we can fully trace back lines , would this be considered ok ?

Absolutely fine. In fact many excellent breeders would consider that too much of an outcross.

Neo 101:  Generation Help:  When the KC Site is available tomorrow after being off line to have technical updates done, check the COI for your intended mating - same area as (tools, look up a dog etc),  NB  Guage by the avg COI for your breed.

> stud dog and bitch have the same great grandfather

That is not an issue in my opinion & probably many other breeders here. They could in theory have the same grandfather, if other on the grandparent line, are unrelated with not too much issue either.

COI's are a tool to use BUT many use differing generations & it should be the same amount to really mean anything. KC COI's don't included foreign dogs within their calculation so results are skewed

Foreign dogs are included, but may only have 3 to 5 generations behind an import or overseas dog, more if some of the dogs ancestors relatives were imported.

Happens a lot in my breed, due to small gene pool, but dogs from same/similar lines have been imported over the years.

So it is rare to have a COI  based on less than 5 complete generations.

Most often you get something like 'this calculation is based on 16 generations, but with 6 being fully complete'.

Ok, I knew it was something odd.
I use our breed archive, which includes all dogs, as it is a worldwide database, so the results are more accurate than the Kennel Clubs COI calculation.

Can't see why KC and other Kennel Clubs that have open pedigree databases, and reciprocal agreements can't cobine data.

Very perochial attutude.