it doesn't really fall into the user-friendly category

By adding a simple wrapper subroutine it gets just as user-friendly as the other functions in this thread. See update.

As far as the splice problem / ... / I mostly handled it since each iteration I check to see if I am falling over the edge

There are other problems as well. You need to consider whether or not you want unshifts to effect your iterator (after you've done a couple of iterations); compare with foreach's behaviour. What's best here may very well depend on the situation. One solution is to just document that you may not do any size-changing modifications of the original array while using the iterator.

ihb

Read argumentation in its context!