It can't be said too much that Abstractions are costly. In the ideal case they're less costly than the alternative, but assuming a Pattern will magically make

It can't be said too much that Abstractions are costly. In the ideal case they're less costly than the alternative, but assuming a Pattern will magically make the code better can itself be even more expensive. Finding the right balance between refactoring and not wanting to make the code harder to understand is always a challenge.