What you are feeling is most likely the abundance of unfermentable dextrins left in the beer. When you start out with a high gravity beer, it is tough to really dry the beer out (especially with extract).
Using a large amount of extract to achieve a high OG should have the same effect. I'd also throw in some Crystal (a # or so) and maybe some carapils. Here's a mini-mash recipe I made that has tons of body (and extremely intense hop bitterness / aroma)
Deck Hops 2009
14-C Imperial IPA
Author: Nick Ladd
Size: 5.0 gal
Original Gravity: 1.084 (1.070 - 1.090)
Terminal Gravity: 1.022 (1.010 - 1.020)
Color: 14.18 (8.0 - 15.0)
Alcohol: 8.22% (7.5% - 10.0%)
Bitterness: 199.4 (60.0 - 120.0)
Ingredients:
3.5 lb 2-Row Brewers Malt
1 lb Crystal Malt 40°L
0.25 lb Crystal Malt 90°L
.25 lb Cara-Pils® Malt
.25 lb Biscuit Malt (Mout Roost 50)
3 lb CBW® Golden Light Powder (Dry Malt Extract)
1 oz Chinook (11.5%) - added during boil, boiled 90 min
1 oz Magnum (12.5%) - added during boil, boiled 60 min
1 oz Chinook (11.5%) - added during boil, boiled 45 min
1 oz Magnum (12.5%) - added during boil, boiled 45 min
1 oz Chinook (11.5%) - added during boil, boiled 20 min
5.33 oz Corn Sugar
3.5 lb CBW® Golden Light Powder (Dry Malt Extract) (Late Kettle Addition)
.75 tsp Irish Moss - added during boil, boiled 15 min
.5 tsp Wyeast Nutrient - added during boil, boiled 10 min
2.0 oz Cascade (5.4%) - added during boil, boiled 5.0 min
0.0 ea WYeast 1272 American Ale II
2 oz Centennial (8.5%) - added dry to secondary fermenter
1 oz Cascade (5.4%) - added dry to secondary fermenter
Actual beer fermented out to 1.014 with the help of a huge start. Grains were mashed @ 152*.
