I've seen Elly Griffiths recommended on MN several times, so I picked up The Chalk Pit the other day. I do think she writes well, and am enjoying her dry humour, but baffled by logistics! The police officers are based in King's Lynn, but they're investigating incidents in Norwich, and seem to be travelling between the two locations in no time at all - which anyone who has spent time in North Norfolk, or even looked at a map, would know is impossible unless by helicopter. Example: two officers are in Norwich getting information, a colleague in KL police station wonders aloud "what's taking them so long" - well, it'll be the hour, minimum, each way on the A47, for a start!
Could it really be feasible that Norwich wouldn't have its own CID department to cover local cases? The author says she spends lots of holidays on the Norfolk coast so she must know how long it takes to get around.