Om Next subquery doesn't have effect on sub component props - clojurescript

Question

Reading this Om Next tutorial page Components, Identity & Normalization, I thought the subquery from the subcomponent (Person component) is used to populate the Person's props. But changing the query from
'[:name :points :age]
to
'[]
doesn't break the app. Could you help me understand how the parser invokes read methods from these component/query tree.
The entire code from the page is below.
(def init-data
{:list/one [{:name "John" :points 0}
{:name "Mary" :points 0}
{:name "Bob" :points 0}]
:list/two [{:name "Mary" :points 0 :age 27}
{:name "Gwen" :points 0}
{:name "Jeff" :points 0}]})
;; -----------------------------------------------------------------------------
;; Parsing
(defmulti read om/dispatch)
(defn get-people [state key]
(let [st #state]
(into [] (map #(get-in st %)) (get st key))))
(defmethod read :list/one
[{:keys [state] :as env} key params]
{:value (get-people state key)})
(defmethod read :list/two
[{:keys [state] :as env} key params]
{:value (get-people state key)})
(defmulti mutate om/dispatch)
(defmethod mutate 'points/increment
[{:keys [state]} _ {:keys [name]}]
{:action
(fn []
(swap! state update-in
[:person/by-name name :points]
inc))})
(defmethod mutate 'points/decrement
[{:keys [state]} _ {:keys [name]}]
{:action
(fn []
(swap! state update-in
[:person/by-name name :points]
#(let [n (dec %)] (if (neg? n) 0 n))))})
;; -----------------------------------------------------------------------------
;; Components
(defui Person
static om/Ident
(ident [this {:keys [name]}]
[:person/by-name name])
static om/IQuery
(query [this]
'[])
Object
(render [this]
(println "Render Person" (-> this om/props :name))
(let [{:keys [points name age] :as props} (om/props this)]
(dom/li nil
(dom/label nil (str name ", points: " points ", age: " age))
(dom/button
#js {:onClick
(fn [e]
(om/transact! this
`[(points/increment ~props)]))}
"+")
(dom/button
#js {:onClick
(fn [e]
(om/transact! this
`[(points/decrement ~props)]))}
"-")))))
(def person (om/factory Person {:keyfn :name}))
(defui ListView
Object
(render [this]
(println "Render ListView" (-> this om/path first))
(let [list (om/props this)]
(apply dom/ul nil
(map person list)))))
(def list-view (om/factory ListView))
(defui RootView
static om/IQuery
(query [this]
(let [subquery (om/get-query Person)]
`[{:list/one ~subquery} {:list/two ~subquery}]))
Object
(render [this]
(println "Render RootView")
(let [{:keys [list/one list/two]} (om/props this)]
(apply dom/div nil
[(dom/h2 nil "List A")
(list-view one)
(dom/h2 nil "List B")
(list-view two)]))))
(def reconciler
(om/reconciler
{:state init-data
:parser (om/parser {:read read :mutate mutate})}))
(om/add-root! reconciler
RootView (gdom/getElement "app"))

Answer 1

From reading this now I know that only the top level queries are processed by the parser. And you are responsible for providing your own reads for subqueries by accessing (:query env).