I learned hiragana 2 years 9 months ago, (on 20 June 2012) and as the article says I started reading stuff written in hiragana quite fast right after I learned.
Today is the first day I began learning katakana. I can already see some pattern. 5 letters of katakana are almost same as their hiragana counterpart. Here you can see how similar these 5 are; (や か り に へ) = (ヤ カ リ ニ ヘ ).
A few katakana letters I can see any how resembling partly to other katakana letters
(lets check ワウラヲフ, they all look ambiguous, WAワUウRAラWOヲHU/FUフ… And I will add some more ambiguities )
Couple of katakana are easy since I see that they match to kanji.
Eg katakana mi ミ is ~ kanji mitsu 三 (San) and ne 礻 is ~ shimesuhen ネ. Also ma マis from ko 子, kodomo. mu ム is a topographic rotation. (and resembles or IS from hotoke 仏 )
Just like that in half an hour 12 katakana character will be remembered for ever.
Plus let’s say katakana ke ケis English kK with little leaning forward.
Few more katakana I happen to know for some or other reason. Eg I practiced writing my name in katakana back in 2002 when I was taking a Japanese course in Japan, although for pressure of particle physics we stopped going after few days.
(my name would buzz like this; マンモハン OR マンモホン)
Also there is a trick I foresee. Take the word keikoto manabu (ケイコト マナブ their website is on my feed) that gives 7 letters to remember easily. If you practice this for 10 times perhaps you will remember the letters.
If you check 1000 words written in katakana, each letters in the set of 46 letters, will get random repetitions. May be varying b/w 10 to 30 for each letter. There are 46 letters. Then you might be as confident as your native language.
I will tell tricks for kanji later.
You = me.
Addendum; here are more and more ambiguities. A comprehensive chart will be added. Also we will see how hiragana also throws such confusions. By keeping them in one place and practicing is a sure shot way of memorizing the alphabet pretty fast. (yes everything finally has to be memorized, understanding just makes it far more efficient)