No. I'd assume it's like this because people who use CLCRet don't go ahead and track the time on their DP proc, so it has them consume it once it's up.
TV DP abides by the same rules as TV 3 would, a little higher even. DP procs only off HP consuming abilities, so as long as you use it before the 8 seconds are up, you should get in your other HP generating abilities first until 5HP, Free GCD, all HP generators on CD, or your DP Buff is about to wear off.