As a SWO-IP option selectee from USNA, I think it behooves anyone trying to join IP/IW to first become warfare qualified, whether pilot, SWO, or subs. The Fleet exposure and knowledge that you obtain in the minimum tour requirement will be invaluable compared to someone coming into the community without it. Regardless if you are COMMO, EWO/CICO (sometimes an LDO billet), or other billet, you will be required to lead, make decisions, and learn from a "firehose" from day one. Additionally, SWO gets you thinking "big" picture and understanding how everything interfaces together, something that is important if you are going into a service providing community.
FYI, service selecting SWO IP does not require any lateral transfer board action, but you do not leave the ship until AT LEAST the completion of your first sea tour (SWO = 27 months).
Also, there was talk at one time that the CNO was considering making the IP community (along with others) URL. I am not sure if that idea was dropped.