Brandon, I used the assist hook off the head quite a bit on a recent trip to Fiji, mainly on cubera 100s and 125s. What I did find, was that after repeated casting the assist cord started to wear a grove in the cup of the popper due to water pressure. Whilst it didn't seam to affect the performance of the popper, it didn't always settle in the dead down position (it might start to wear to one side for example).
I can imagine over time the wear will severely compromise the paint coating and lead to water logging of the popper! Luckily?, I was losing poppers to being reefed more often than changing them due to water logging. Have you experienced this, and what have you done to combat it?
PS. I also found that an assist of the head and a spinner off the tail to be a good balance on some poppers.