diff --git a/app/models/course.rb b/app/models/course.rb
index 2e55a93c9..db856ad61 100644
--- a/app/models/course.rb
+++ b/app/models/course.rb
@@ -68,6 +68,11 @@ def visible_events
     events.visible
   end
 
+  # @return [Event::ActiveRecord_AssociationRelation]
+  def projectable_events
+    events.used_for_projections
+  end
+
   # @return [String, nil]
   def home_time_zone
     events.latest&.home_time_zone
diff --git a/app/models/event.rb b/app/models/event.rb
index 2d227a563..94d15af81 100644
--- a/app/models/event.rb
+++ b/app/models/event.rb
@@ -43,6 +43,7 @@ class Event < ApplicationRecord
   after_touch :notify_event_update, if: :topic_resource_key?
 
   scope :name_search, ->(search_param) { where("events.name ILIKE ?", "%#{search_param}%") }
+  scope :used_for_projections, -> { where(use_for_projections: true) }
   scope :select_with_params, lambda { |search_param|
     search(search_param)
       .left_joins(:efforts).left_joins(:event_group)
diff --git a/app/models/projection.rb b/app/models/projection.rb
index 892661a80..e71c4ecf8 100644
--- a/app/models/projection.rb
+++ b/app/models/projection.rb
@@ -39,11 +39,10 @@ def self.sql(split_time:, starting_time_point:, subject_time_points:, ignore_tim
         relevant_event_ids as (
           select events.id as event_id
           from events
-            join event_groups on event_groups.id = events.event_group_id
             join courses on courses.id = events.course_id
             join splits on splits.course_id = courses.id
           where splits.id = #{starting_split_id}
-            and (event_groups.concealed is false or event_groups.concealed is null)
+            and events.use_for_projections is true
             and (#{ignore_timestamp} is null or events.scheduled_start_time <= #{ignore_timestamp})
           order by scheduled_start_time desc
           limit #{EVENT_LOOKBACK_COUNT}
diff --git a/app/parameters/event_parameters.rb b/app/parameters/event_parameters.rb
index 4420dea5e..c6d1bb088 100644
--- a/app/parameters/event_parameters.rb
+++ b/app/parameters/event_parameters.rb
@@ -14,6 +14,7 @@ def self.permitted
       :results_template_id,
       :notice_text,
       :lottery_id,
+      :use_for_projections,
     ]
   end
 
diff --git a/app/view_models/plan_display.rb b/app/view_models/plan_display.rb
index 16819fa8b..3c959c41d 100644
--- a/app/view_models/plan_display.rb
+++ b/app/view_models/plan_display.rb
@@ -3,18 +3,26 @@ class PlanDisplay < EffortWithLapSplitRows
 
   include CourseAnalysisMethods
   include TimeFormats
+
   attr_reader :course, :error_messages
 
   delegate :name, :organization, :simple?, to: :course
   delegate :multiple_laps?, to: :event, allow_nil: true
 
-  def initialize(args)
+  def initialize(args) # rubocop:disable Lint/MissingSuper
     @course = args[:course]
     @params = args[:params]
     @error_messages = []
     validate_setup
   end
 
+  # Overrides CourseAnalysisMethods#event: planning anchors on the same
+  # events the projection engine draws data from, so a course whose only
+  # events are concealed seed events can still plan
+  def event
+    @event ||= course.projectable_events.latest
+  end
+
   def effort
     @effort ||= event.efforts.new
   end
@@ -103,7 +111,7 @@ def lap_splits
   end
 
   def validate_setup
-    error_messages << "No events have been held on this course." if course.visible_events.empty?
+    error_messages << "No events on this course are available for planning." if course.projectable_events.empty?
     AssignSegmentTimes.perform(ordered_split_times) if error_messages.empty?
   rescue ArgumentError => e
     error_messages << e.message
diff --git a/app/views/events/_form.html.erb b/app/views/events/_form.html.erb
index 8dd328faa..1aacc8fac 100644
--- a/app/views/events/_form.html.erb
+++ b/app/views/events/_form.html.erb
@@ -197,6 +197,17 @@
               <%= form.text_field :beacon_url, class: "form-control", placeholder: "example.com/tracking/my-event" %>
             </div>
           </div>
+
+          <div class="row">
+            <div class="mb-3 col">
+              <%= form.label :use_for_projections, "Use this event's times for projections", class: "me-2" %>
+              <span tabindex="-1"
+                    data-controller="tooltip"
+                    data-bs-placement="bottom"
+                    data-bs-original-title="When checked, this event's split times help power pacing plans and live projections for events on this course, even if this event is not public. Uncheck if this event's times are unreliable (for example, unrealistic test data or serious timing problems) and should not influence predictions."><i class="fas fa-circle-question"></i></span>
+              <%= form.check_box :use_for_projections %>
+            </div>
+          </div>
         </div>
 
         <br>
diff --git a/spec/models/projection_spec.rb b/spec/models/projection_spec.rb
index cf9bf4986..de1f00b88 100644
--- a/spec/models/projection_spec.rb
+++ b/spec/models/projection_spec.rb
@@ -85,6 +85,22 @@
       end
     end
 
+    context "when an event on the course is flagged not to be used for projections" do
+      before { events(:hardrock_2014).update_column(:use_for_projections, false) }
+
+      it "does not draw from that event's efforts" do
+        expect(subject.first.effort_years).to eq([2016])
+      end
+    end
+
+    context "when an event in a concealed event group is flagged for projections" do
+      before { event_groups(:hardrock_2014).update_column(:concealed, true) }
+
+      it "draws from that event's efforts" do
+        expect(subject.first.effort_years).to eq([2014, 2016])
+      end
+    end
+
     context "when given a starting split time" do
       let(:split_time) { effort.ordered_split_times.first }
       it "returns an empty array" do
diff --git a/spec/system/plan_effort_flow_spec.rb b/spec/system/plan_effort_flow_spec.rb
index 4b404848b..dc4ce4fe1 100644
--- a/spec/system/plan_effort_flow_spec.rb
+++ b/spec/system/plan_effort_flow_spec.rb
@@ -50,11 +50,11 @@
       visit_page
 
       verify_content_present(course)
-      expect(page).to have_content("No events have been held on this course.")
+      expect(page).to have_content("No events on this course are available for planning.")
     end
   end
 
-  scenario "Inputmask works", js: true do
+  scenario "Inputmask works", :js do
     visit_page
 
     expected_values = {
diff --git a/spec/view_models/plan_display_spec.rb b/spec/view_models/plan_display_spec.rb
new file mode 100644
index 000000000..6b9cd2da3
--- /dev/null
+++ b/spec/view_models/plan_display_spec.rb
@@ -0,0 +1,32 @@
+require "rails_helper"
+
+RSpec.describe PlanDisplay do
+  subject { described_class.new(course: course, params: ActionController::Parameters.new(params)) }
+
+  let(:course) { courses(:hardrock_ccw) }
+  let(:params) { { expected_time: "38:00" } }
+
+  context "when the course has visible events with relevant data" do
+    it "returns no errors and builds projected split times" do
+      expect(subject.error_messages).to be_empty
+      expect(subject.ordered_split_times).to be_present
+    end
+  end
+
+  context "when the course's only event is in a concealed event group but flagged for projections" do
+    before { event_groups(:hardrock_2015).update_column(:concealed, true) }
+
+    it "returns no errors and builds projected split times" do
+      expect(subject.error_messages).to be_empty
+      expect(subject.ordered_split_times).to be_present
+    end
+  end
+
+  context "when no events on the course are flagged for projections" do
+    before { course.events.each { |event| event.update_column(:use_for_projections, false) } }
+
+    it "returns an error message" do
+      expect(subject.error_messages).to include("No events on this course are available for planning.")
+    end
+  end
+end