Ah, I assumed he was doing AG since he said he just did an AG batch and it turned out the same as the extract batches.
But sure, to eliminate water as the problem RO/distilled will work really well.
Also, he never really mentions what is so bad about the beer. Is it just overly bitter or are there other problems? IMO, there are a lot of things beginning brewers can do that would make their beer turn out bad and water would not be at the top of the list.
Fermentation temperatures and sanitation practices and time always come to mind first.
Also, it might be helpful to see the city's water quality report.
I lost track of this post for a few days. I agree blaming water is a stretch.
I can explain a little more of what happened. But first, to address the post about the sulphate and chloride ratio not having an affect. I listening to all four parts of the Brew Strong podcast on brewing water, and Palmer explicitly stated that the sulphate to chloride ration can effect the taste of the beer. He also explicitly states that water adjustment is also effective in extract brewing.
The first beer I brewed was a Irish Red Ale. After posting I realied that for this one I actually used bottle water, but it was spring water, not distilled, and I don't know what the mineral profile was. But this beer came out very bitter for an Irish red. I thought it was the recipe, since it did have a higher IBU than a normal Irish red. This beer was in the fermentor for about two weeks. The OG and SG were in range. I just recently dumped it, but it was in the keg for about 4 months. The bitterness reduced a little bit over time, but even up until the 4 months it was defintely too bitter for an Irish Red. Honestly, I couldn't tell if there were any other off flavors because of the strong bitterness.
After being unhappy with the first batch I tried to brew the maltiest batch my LHBS had, and that ended up being a Scottish Ale. I kept this one in the fermentor for 6 weeks. The OG and SG were in range. This one I actually tasted before kegging, and it was very sweet. For this beer, I used carbon filtered tap water. However after a week in the keg, it started to acquire a bitterness. In fact the flavor and bitterness levels were very very similar to the Irish Red that I had made, with the Scottish being a less harsh bitterness. I kept this on in the keg for about 2 months, and the bitterness never faded.
I also bottled both beers at different times, and I found that out of the bottle, some of the beers would be more bitter than others, and some would be not that bad in terms of the bitterness. To me, this doesn't make any sense, but I did have a few people confirm this phenomenon.
Like I said, I would say the chance of the water being the problem, is very slim, however, except for oxidation, I have not found too many other source of uncommonly strong bitterness in a finished beer.
One other flaw that existed in the beer was terrible head retention. And when the foam dissipated, it left very ugly almost curdled looking lacing on the top of the beer. From the pictures I have seen it wasn't as bad as infection, but it definitely wasn't pretty.