I agree it could be difficult, especially as one is supposed only to listen out on frequency in the hold and then make first call on final, so no chance of getting any picture from radio transmissions. That's partly why I chose an early slot at 0930.
I still don't know whether to go to Pitsford and then turn towards the airfield straight away, or do one holding pattern and rely on Mk1 eyeball to see if anyone else is about before heading in behind anyone I judge to be in front of me.
Wycombe seemd a whole lot simpler.