@philfrei Thank you. Yes, it dawned on me when I woke up in the middle of the night and was trying to fall back asleep. <? extends T> is any class that, well extends T, lol. <? super T> is any class that is extended by T. Now I have the concept on lockdown.
I found this floating about after reading the thread. It had some interesting comparisons: http://stackoverflow.com/a/26514984/7323222
Everyone is obviously at different stages of development, but I’ll be using the easier-to-follow instanceof until I personally see bottlenecks.