you're probably referring to mudbutt. as im sure many people do, i prefer to time my poops so that they are right before my shower. when i am regular, this all happens as part of my morning routine (thanks oatmeal/yogurt).
Urban Dictionary: mudbutt
however i would never short change my wiping and see the shower as an alternative. to me, TP and shower and complements rather than substitutes:
Complementary good - Wikipedia, the free encyclopedia
Substitute good - Wikipedia, the free encyclopedia
OK, so you like both wiping and shower...almost as an 'all start' team working together. That's great timing on your part.
Has there ever been a time (not before a planned shower) when you had to poop, leaving yourself with severe mudbutt? After attempting the first wipe you notice an enormous amount of 'mud'.
Feeling dis-hearted at the huge task you have ahead of you...you decide it's time for a nice refreshing shower, thus solving the issue?