I was wondering about that. I can see the need for going slow when acclimating, but if ph and temp and TDS etc are all similar, I wasn't sure if there was any reason to add water slowly during a water change. So if I reminerized my water it would be ok to pump it in, maybe with a valve to slow the flow a little?
If your new water has similar parameters as your tank water, I see no reason you can't pump it in.
I've never had a problem with it in the past but it's your decision at your own risk. My remineralized water has a fairly low pH and my UGF system buffers it quick. Oh and I don't heat it to tank temp either......