Since your logs aren't actually difficult to find, I thought I'd take a peak and see just how bad this lock supposedly is. This other lock seem to have caught the basics of the spec, however he's bad at paying attention to short cooldowns and dot durations. Apart from the choice of pet it's only a lot of small things like not using HoG on cooldown, dot uptimes, lower item level, using NF over MWC, not timing DG with procs and generally a lot of small things adding up to a lot.
I would try teach him the small neat things like optimal usage of DG and advice him to watch his timers more closely and work proactive instead of reactive. If that helps him, that is good, if not then at least you made some small effort in helping.
Here's a comparison for those that might be interested: