Bergerman, as far as I know, the relatively small amounts of 'propoline glycol' (sp?) - i.e. pool and rv antifreeze- added to a pool as the result of winterizing, have no ill effects on the water. To the best of my knowledge, it does not effect the normal testing perameters - pH, alk, etc.. I can't recall reading any negative or disparaging posts here on letting it just mix with the pool at the opening of the season.
However, if you are reluctent to let it mix, by all means waste out what's in the skimmers when you start the pool - any in the return lines would be harder to keep out of the pool.


So in short, as with all things you may want to do with your pool - it's your pool, your money and (if you do something wrong) your problem to fix - and if you don't feel comfortable letting antifreeze mix with the water, then by all means dump it.