Yeah, it'll be insane. I've found that kit-wise, dry-hopping at 20g/22L is usually noticable enough and anthing over 30g/22L can be quite powerful. This is especially true of those higher alpha acid hops such as PoR. In the past I have found PoR dry-hopping to be unpleasant, although I don't mind it as a bittering or flavour addition.
I'd suggest a good 'Coopers Pale' kit recipe as follows:
The 1.7kg can
500g LDME
300g white sugar
10g PoR boiled (with a tablespoon of the LDME) in 500ml water for 15min and then the whole lot added to the fermenter. Use 20g if the AA rating is only 5 to 7%.
As for the experiment...let us know how your 5g/750ml thing goes!
- boingk