Has the handling of my_hdr and send_hook changed between 1.10.x and 2.1.4?

[cl]

I'm trying to sort out why something that used to work for me no
longer works.  I just went and tried out an older installation that
still runs mutt 1.10.4 and there my send-hook/my_hdr configuration
works. It doesn't work on my current mutt 2.1.4.

I see the documentation now says "Also note that my_hdr commands which
modify recipient headers, or the message's subject, don't have any
effect on the current message when executed from a send-hook.".  Is
this a recent change?

I'm not doing anything very clever, I just have:-

    #
    #
    # set default my_hdr according to which host we're on
    #
    send-hook . 'my_hdr From: Chris Green <$my_addr>'
    #
    #
    # set From: address for mailing lists, not sure if it actually works on 
cheddar
    #
    send-hook ~l 'my_hdr From: Chris Green <c...@isbd.net>'

... in my muttrc file so that my From: address for use with mailing lists is
different from my default From: address.

This appears to no longer work.

How should I do this now?

-- 
Chris Green