dwhite60
Landlord.
Totally do this.
Boil 1.5kgs Light DME in 12ltrs water for an hour and add bittering, taste and nose hops at your discretion. Add another 1 to 1.5kg DME in the last 15, cool and add to your fermenter to make 23 ltrs of IPA style beer of your making. (Pitching yeast obviously which is another factor you can experiment with. Use Safale US-05 as the starting point)
Use a chart like this to play about with hops.
http://www.cliffsnotesbeerguide.com/wp-content/uploads/hop-chart.jpg
I made a cream ale this year and added all the hops (Amarillo) twenty minutes before end of boil. I got it all, bitter, flavor, and some aroma. No need to boil an hour if you put enough in. Takes more to get the same bitterness as an hour boil gives but makes a slightly easier brew day.
I read Sierra Nevada does similar with their pale ale. All the hops go in at the end of the boil.