Several things to bear in mind. (I might even have been on sector and worked you) (What time was it?)
1 - Tay Sector would want to know if you were IFR/VFR as it may determine whether you would need handing to Edinburgh for a radar letdown or routing via VRPs. As said earlier, Tay would generally try and keep you beneath the Talla sector (ie 6000 or below) as the fast stuff is descending on top of you to MinStack level (usually FL70 or FL80) - this keeps you separated vertically, avoids overloading Talla, and in which case you could then be handed direct to Edinburgh.
2- While it may appear to be a 'handover' from Newcastle, it might well have been with very short notice to Tay. Was it a Scottish 'local' 3626/3627 squawk or an airways squawk?
3-Tay can be incredibly busy over a diverse area, with most concentration around P600 into Aberdeen, the NEW VOR roundabout (crossing airways into/out of Glasgow/Edinburgh and Manchester/Scandinavia), avoiding of and passing info on the numerous fast jets whizzing around attacking Eastern Airways Jetstreams east of Leuchars - after all that ... it is fair to say that VFR traffic outside CAS and particularly at lower levels is the lowest priority.
4-Controlled Airspace base levels (and boundaries) have been changed (by office types who don't have to remember it all) so many times in recent years, and indeed on many of our maps there are different levels for different times of the day, that it can be tricky to remember all the bases/fillets without having to double check on the meticulously accurate sector maps.
5-Numerous Danger Areas in the area with variable times and levels would probably be checked on our notoriously easy to use Danger Area pages
6-So perhaps any 'hesitation' on the part of the controller might be because they were checking Danger Area activity (to make sure you ain't going into an active area), checking that you are not going into Class A airspace, co-ordinating with the TMA controllers/ then Edinburgh Radar/ and perhaps the FIR controller, and agreeing a course of action ... and then of course separating the other 8 aircraft on frequency ... ?
7-Cumbernauld inbounds are not that frequent. I see perhaps one a month.
8-lack of issuing clearance? Yup, technically you need one for entering the 2 Class D TMA fillets, so controller was possibly just busy and an oversight, as 95% of our traffic doesn't need a joining clearance - but you are quite right to query that.
Hope that answers your Qs ? Anyway, next time fly over to PIK and come and have a look round ...
