I just dealt with fixing V roller issues on my Ender 3, and got to questioning the eccentric nut setup. It's hard to get perfect tension without overtightening (possibly leading to flat spots) and tension needs to be adjusted periodically as they wear. And it occurred to me that the rollers could potentially be tensioned against the extrusion grooves with springs rather than an adjustable eccentric nut.
Is this a setup that's been tried? Are there reasons not to use springs here, other than likely costing a bit more?