Background: I taught myself Simplified over forty years ago. The only times I ever used it to take dictation were in the course of a three-week summer job. I have, nevertheless, continued to use it for note-taking ever since then. Out of curiosity I have learned, over the years, to read Anniversary, and I have borrowed some shortcuts from the Anniversary edition--chiefly for words that are cumbersome to write out. I have even chosen to use the reversing principle before t, m, and n.
In Gregg Dictation Simplified appears an essay by Martin J. Dupraw called "Shorthand Speed." The essay seems to be an apology for the 1949 revision of the system. In answer the the question "Wouldn't more shortcuts help?" Dupraw wrote, "A few shortcuts for the most frequently recurring words are necessary. Beyond that small list every shortcut is much more likely to be a hindrance than it is to be a help...the longer I write shorthand the longer I write shorthand." Specimens of Dupraw's notes, on the other hand, show that he used myriad shortcuts--far more than those provided in the Anniversary edition of the Manual.
My observation is that I am able to recall shortcuts faster than I can construct longer outlines. My reasons for not converting wholesale to Anniversary are (1) That when I try to do so, I often find myself starting to write a simplified outline, hesitating, and then writing the Anniversary outline, and (2) That I think some Simplified outlines are superior, as for example, those for "report," "represent," and "representative." The simplified outline for "represent" is quite logically derived from the outline for "present." Furthermore, no general principle calls for writing "pr" for "port." (3) That sometimes the same outline represents one word in Anniversary and another in Simplified, as, for example "control' (Anniversary) / "quality" (Simplified), and "reserve" (Anniversary) "receive" (Simplified).
I think an ideal edition would incorporate many of the changes made in Simplified but retain all the analogical word beginnings and endings from Anniversary, a number of the brief forms, and a limited use of the reversing principle. Needless to say, not such edition is likely to be published.
The only thing good about Diamond Jubilee is that not turning the "o" on its side before "r" and "l" probably increases legibility. Is it an impediment to speed? Probably only for the fastest writers.