I've been doing my own little experiment (of sorts) whereby to assess the bitterness and/or dryness attributable to mineralization. Two of my favorite lagers are Pilsner Urquell and Great Lakes Dortmunder Gold. Pilsner Urquell is rated at 40 IBU, and is 'presumed' to be the product of water with almost no mineralization to speak of. Dortmunder Gold (which rates at 30 IBU's) is similarly (to me) malt forward, and has a similar light orange color to Urquell (call it gold), and a similar mouthfeel, but for the Dortmunder style it is 'presumed' that one must begin with water that is over the top high with respect to being across the board mineral rich. I've 'critically' drank them side by side three times now. Both taste quite similar to me in many ways when drank alone. My presumption going in was that 30 IBU's plus massive mineralization would taste more bitter and dry and crisp than 40 IBU's and zip for minerals (it might as well be RO or distilled). But this isn't even close to being the case. Despite their very similar overall malt taste (which to me comprises a big part of what I perceive as mouthfeel), the Urquell has pronouncedly more hop bitterness, and also noticeably more crispness (dryness). How can this be if Urquell's source water almost completely lacks sulfate, and every other mineral to boot? When I do this test I sip the Dortmunder first, and it is mega delicious. Then I sip the Urquell and it is even more mega delicious. Then from that point forward the mineral rich Dortmunder tastes flat and muted, and is everything that a mineral free beer should be (per the textbooks and their parrots).