The Association of Canadian Mountain Guides demonstrate Fixed-Point belay systems in this video.
Fixed-point belay systems as demonstrated make no effort to equalise the loading on the two anchors, but the video also states several times that fixed-point anchors are only appropriate for solid gear: bolts or ice-screws.
Fixed-point belay systems don't follow SERENE (or ERNEST). Why is this?
When considering 'bomb-proof anchors' in rock (bollards, for example, that have significant ratings [upwards of 80kN]), using two anchors in this fashion might allow for more ideal placement of the belay point: directly on an anchor, rather than between two anchors. If a single anchor is extremely unlikely to fail, this seems reasonable; I'm happy belaying off a single bollard in our area.
What is different about ice climbing? Are ice-screws considered stronger than natural protection in traditional rock climbing? What are the advantages of ignoring equalisation and creating fixed-point belay systems?