"Multiple runs on syslocks when lock counts are high can stress out the server."
Do you have some evidence to back that up? My tests show the exact opposite, monLocks is the problem one.
Agreed it does save on materialisation, you need to make sure you've got a couple of GB spare in your assigned tempdb if you have millions of locks and are querying syslocks.
When the server has millions of locks querying monLocks is impossible if you want results in an acceptable timeframe ( and can't afford an engine being essentially offline for that period)
