Upward Sloping, Imm RPR < YTM, Lower Reinvestment?

Book 4 Upward Sloping Yiled Curve, Immunized Target Rate of Return < YTM, therefore lower reinvestment risk I am trying to figure out the cause & effect of above. I mean is the upward sloping yiled curve the reason for the ITROR < YTM, Is the reason for the lower reinvestment rate the ITROR < YTM or is it because of the upward sloping yield curve. The only logical explanation I found was upward sloping yield curve means short rates are less than long rates. Since most immunizations are short term in nature ( 5 years or less) the reinvestment of coupons are being placed at the lower end of the curve. but then at 4 am this morning, i figured I better not make notes on these conclusions without actually knowing the real answer, because it may not have anything to do witht he yield curve at all but simply lower reinvestment rates earned since ITROR is < YTM Help !!

http://www.analystforum.com/phorums/read.php?13,1093118,1094281#msg-1094281

elcfa Wrote: ------------------------------------------------------- > http://www.analystforum.com/phorums/read.php?13,10 > 93118,1094281#msg-1094281 Thanks again EL. So from reading the post ( the detailed calculations are too much for me too hanlde, ( so Upward sloping, shorter rates are less than longer rates, i.e less reinvestment return) ok, hopefully that will be enough