I like your idea of draining the slaw. That way you get some of the bad stuff out but, still have most of the flavor and the healthy, cruciferous cabbage. My mom , who tries to maintain a very low fat diet, actually rinses it. I guess much of the flavor is lost that way but, you do what you gotta do. Salw made with just oil and vinegar (no mayo) is good too.
The following is from foodreference.com.
COLE SLAW, COLD SLAW
The reason cole slaw became as popular a side dish as it did in America was due to NYC deli owner Richard Hellmann's 1903 creation of a formula for bottled mayonnaise, which he began marketing in 1912. It became a bestseller, quick and easy to use as a dressing for shredded cabbage, which thereafter became a standard side dish to the increasingly popular sandwiches and hamburgers in American kitchens.
‘American Classics: Cole Slaw’, by John Mariani,
Restaurant Hospitality Magazine 1/97
Cole slaw (cold slaw) got it's name from the Dutch 'kool sla' - 'kool' is cabbage and 'sla' is salad - meaning simply, cabbage salad. In English, that became 'cole slaw' and eventually 'cold slaw'. The original Dutch 'kool sla' was most likely served hot.