-Each insertion command key sequence begins (disregarding prefix
-arguments) with @kbd{i}, followed by one or more of these eight keys, in
-the order listed. But as you can see in the above table, since some of
-the insertion parameters are mutually exclusive, they occupy only five
-positions, so the complete (unprefixed) sequences are maximally six keys
-long. Shorter sequences are also possible, since a parameter may be
-omitted. But since the order in any key sequence is fixed, if the last
-key in the sequence could be followed by another insertion key, i.e., if
-the last key is not @kbd{h} or @kbd{r}, it has to be doubled to complete
-the sequence, otherwise it would be interpreted as a prefix sequence
-(this is why the binding for the basic item insertion command is @kbd{i
-i} and not @kbd{i}).
-
-Here are some examples of item insertion command key sequences:
+Note that the parameters are divided into five numbered groups; within
+a group, the parameters are mutually exclusive. Hence, to build a
+complete insertion operation, you select at most one parameter from at
+least one of these groups, by typing the corresponding key. If you
+want to apply more than one parameter, you must type the corresponding
+keys in the order of the numbered groups, subject to the following
+constraints.
+
+The keys of groups 2-4 are continuation keys, that is, each can be
+followed by a key from a following group. If you want to finish the
+sequence with a continuation key, you must double the final key. For
+example, @kbd{i y} is not a complete key sequence; rather, you must
+type @kbd{i y y}.
+
+By contrast, the keys of groups 1 and 5 are final keys; for example,
+@kbd{i i} and @kbd{i h} are complete sequences. The reason for making
+two separate groups of the final keys is that the parameters
+@samp{default} and @samp{copy} cannot be combined with any other
+parameters, while @samp{here} and @samp{region} can be combined with
+any of the parameters from groups 2-4.
+
+To aid you in building item insertion key sequences, when you type an
+insertion key, this displays a prompt in the echo area showing pairs
+of the remaining possible keys and their associated parameters,
+grouped and ordered in accordance with the above list. The initial
+prompt, after typing @kbd{i} to invoke @code{todo-insert-item}, looks
+like this:
+
+@example
+Press a key (so far `i'): @{ i=>default p=>copy @} @{ y=>diary k=>nonmarking @} @{ c=>calendar d=>date n=>dayname @} t=>time @{ h=>here r=>region @}
+@end example
+
+@noindent If you now type @kbd{y}, the prompt changes to this:
+
+@example
+Press a key (so far `i y'): y=>diary:GO! @{ c=>calendar d=>date n=>dayname @} t=>time @{ h=>here r=>region @}
+@end example
+
+@noindent Notice that the pair @samp{k=>nonmarking} is now absent, since it
+belongs to the same group as the selected pair @samp{y=>diary}, hence
+is no longer available for this sequence. Since @kbd{y} is a
+continuation key, it is still available, but now the string
+@samp{:GO!} is appended to the pair to remind you that pressing this
+key again will complete the sequence.
+
+
+
+@c Here are some examples of item insertion command key sequences:
+
+@c @itemize @bullet
+
+@c @item
+@c @kbd{i h} inserts a new item at the position of the item at point (pushing
+@c the latter down) with a header containing the current date and,
+@c depending on the values of the mentioned options, possibly the current
+@c time and diary-related markings.
+@c @item
+@c @kbd{i y h} does the same as the preceding command, except that
+@c @code{todo-nondiary-marker} is added if @code{todo-include-in-diary} is
+@c non-@code{nil} and omitted if that option is @code{nil}; that is,
+@c the diary key @kbd{y} @c overrides the setting of this option.
+@c @item
+@c @kbd{i y t h} does the same as the preceding command, except that it
+@c prompts for a time string instead of automatically inserting the
+@c current time; however, typing @key{RET} at the prompt returns the
+@c current time if @code{todo-always-add-time-string} is non-@code{nil},
+@c otherwise the empty string (i.e., no time string).
+@c @item
+@c @kbd{i y t t} does the same as the preceding command, except that it
+@c prompts for the item's priority and inserts it accordingly.
+@c @end itemize
+
+
+An alternative to the key sequence @kbd{i c c} for choosing the item's
+date from the calendar is also available: when point is already on a
+date in the calendar, typing @kbd{i t}
+(@code{todo-insert-item-from-calendar}) prompts for a new item and its
+priority and inserts it in the current category. This command, like
+@code{todo-insert-item}, also accepts one or two prefix arguments for
+choosing the category via minibuffer completion. Note, however, that
+the key sequence @kbd{i t} is not defined in Todo mode but in the
+Calendar mode keymap. It is a convenient shortcut if you happen to be
+using the calendar when you decide to make a new todo item. (Contrast
+this with passing the @samp{calendar} parameter, which pops open the
+calendar after you have entered the item's text, and then you can
+choose a date from the calendar.)