Makes me wonder if it would have been smarter to build it in a modular way with different pieces being sent up one at a time, assembled on the ISS, then launched in the direction it needed to go.
The biggest problem would be that it would be in the ISS orbit, which would require a lot of delta-V to get it to its final orbit.
Not only would they be replaceable, but we could increase capacity in the future.
For those who don't know what the quote is. I found it here[1].
[1]: http://www.ganssle.com/articles/programmingquotations.htm
Having worked both in construction and software, modular design seems fairly common in both.