Learner SC,
It is an interesting approach! I believe the Lau romanisation was invented by Sydney Lau (劉錫詳). Later on, a couple of romanisations were invented or introduced: WSL proposal, HKIEd proposal (based on WSL proposal), LSHK (or Jyutping developed by Linguist Society of Hong Kong), etc. And some textbooks take the liberty to further adjust the symbols or tones based on them. I called them "proposals" because HK Government almost never made any of them official.
In my opinion, it should be an interesting read but you should also be aware of the changes of pronunciation, the choice of words and expressions by native speakers over the time, since Lau's romanisation was created in the 60s, and Cantonese, no matter in Hong Kong or Guangzhou or all over the world, already changed tremendously, needless to say the effects of IT which changes our life upside down (or it is impossible for us share our thoughts here now :-D), so I may suggest you to have a look at the "new" romanisation systems, which i think reflect the current pronunciation better.