..."Palmer's spreadsheet told me I need more alkalinity, so I dumped a bunch of chalk in my mash." They almost never actually need the chalk, and end up doing more harm than good.
Sounds like a quote from someone who didn't understand how to use the tool.
Which brings up a good point - I think the reason "Bru'n Water" is a more effective app than Palmer's is that, when you take the time to read the instructions and technical background given, its easier to understand and wield to your usage level.
To do it right, you need to understand WHY you're adding brewing salts.
Just throwing in salts because "the spreadsheet says I need more alkalinity" or "my pH strip isn't the right color" is an easy way to throw off your beer before the brewday even starts.
Every brewer should make the decision to either geek out and spend an hour (or two) to read and understand water chem., or buy a mix of distilled and spring water. Either can make great beer - it just depends on how much control you want over your brew and your level of interest in the science behind it.