This is just a rough idea, but I've seen Polemo doing keep raid few times without cutting the port in the past.
Of course it was when Alb zerg had crazy amount of number compared to the enemy BG.
But it was interesting to see, for example, him sieging Glen when mids were free to port inside the keep.
I believe he was just doing it for fun, taking risk for nothing actually.
Maybe he was bored to see no resistance for hours.
My suggestion here is, what about giving incentive for attacking a keep without port cut?
For example, just taking Berk keep without taking Berk gt/wt/op in advance.
Maybe it can be granting twice the rps for taking a keep, or twice the rp pool,
or even getting all the towers of the keep at once when the keep is taken.
I know this kind of situation won't happen that often, but there are definitely some times when the population imbalance is kinda huge.
So, I think this can give a reason for the dominating BG to take a risk, instead of boring but safe routine(cutting ports by taking towers before keep siege).
Also, this might create more action in defender pov, cuz overwhelmed realm can port to the keep freely and safely.
Even the people who aren't interested in defending the keep might wanna try it, cuz, you know, port is easy and you get into instant action.
Enabling one more possible tactic by giving some incentive won't be bad at least for both realm.
Of course it was when Alb zerg had crazy amount of number compared to the enemy BG.
But it was interesting to see, for example, him sieging Glen when mids were free to port inside the keep.
I believe he was just doing it for fun, taking risk for nothing actually.
Maybe he was bored to see no resistance for hours.
My suggestion here is, what about giving incentive for attacking a keep without port cut?
For example, just taking Berk keep without taking Berk gt/wt/op in advance.
Maybe it can be granting twice the rps for taking a keep, or twice the rp pool,
or even getting all the towers of the keep at once when the keep is taken.
I know this kind of situation won't happen that often, but there are definitely some times when the population imbalance is kinda huge.
So, I think this can give a reason for the dominating BG to take a risk, instead of boring but safe routine(cutting ports by taking towers before keep siege).
Also, this might create more action in defender pov, cuz overwhelmed realm can port to the keep freely and safely.
Even the people who aren't interested in defending the keep might wanna try it, cuz, you know, port is easy and you get into instant action.
Enabling one more possible tactic by giving some incentive won't be bad at least for both realm.