Strange verb string tonal pattern

As you say I think the tendency is to descend in pitch as you read any list:

I'll have a Big Mac, fries, Coke and a sundae.

Unless one is speaking in a monotone the last item might be emphasised by a rise in pitch.

An exception to this might be if the speaker is intentionally drawing attention to each item in the list in an exaggerated manner, such as an emcee, TV show host or other professional speaker.

Julie's talents include dancing, singing and playing the banjo.

Try saying the above sentence such that there is a rise in pitch from 'dan' to 'cing', another rise to 'sing' but then a drop to 'ing', followed by a gradual descent in 'playing the banjo'.

This is difficult to describe in words!