I always do almost the same thing.
When my wife or I have good service from a tipped employee, we will leave two separate tips: a miniscule one for the record and then a far more handsome one for the service provider (cash to go in the pocket).
The reason for this is the tendency in a lot of places to pool tips (not skimming by management) and for taxes. When we tip, we want to tip the person who provided the service, not every employee in the establishment.
I LIKE that idea ... thanx.