Decoction is controversial enough that you won't get a straight answer here. I personally am in the camp that if you focus on a perfect fermentation, you'll make a great beer. For my Oktoberfest that I'm brewing next month, I'll be adding 1/4lb Melanoidin, but more to add complexity than replicate a decoction.
If you want to go through the whole decoction process, go for it. If not, you can still make a killer beer.
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Secondary: Sour Red, Saison Tarté Noire, Flemish Red A/B, Flemish Oud Pale, Sour Experiment A/B/C/D
Kegged: Summer Spiced Saison, Rakau Pale Ale, Saison d' Tablé, International IPA, Belgian Witbier
Bottled: OaksterDAMN Barleywine, Saison Noire, Royale with Cheese, Awkward Encounter Wild Ale