Decrypt - beta!

I've always been interested in Cryptography and have written a few
programs that deal with it, but never gotten very far. But one day
I was thinking about Cryptography again and found my way to some
cryptography forums and came across this post:

=========================================================================
The other night, my father and I were looking through his 1974 yearbook,
and just as he was about to put it away, I noticed something interesting.
Back in the section where family and friends write words of encouragement
to the graduates, I saw this listed as an entry:

310411300410, 301 --- 400411610201 --- 701411601, 401301311201 - AIGD

I'm no cryptologist, but I took a stab at solving it, which only led to
extreme frustration with very little success, despite trying many, many
different methods of analysis. This has been bugging myself
(and 3 other people) for a while now -- can anbody help decode it?
=========================================================================

Almost immediately after, some on posted the decrypted text:

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Your decoded message is this

John I --- love --- you, Mike 1974

Reply if you want to see how I decoded it
=========================================================================

The other guy never replied and that’s where the thread died. I was very
interested by then because at first glance it looks totally impenetrable
to my mind. So I set out to re-construct the key using the decrypted text.

Looking at it now it actually looks really really easy! Turns out that
there are several features about the specific encoded text that serve as
weaknesses you can use to begin cracking it. You literally only have to
decode 2 or 3 letters correctly and the entire encryption scheme falls
apart.

So here is the final cryptanalysis and key:
===========================================
The digits are easy. Each letter encodes a single digit:

A B C D E F G H I
1 2 3 4 5 6 7 8 9

Next, the text was a bit more difficult, but only slightly.
First thing to notice is the strings of #s are clearly too long
to be words if it's simply a 1 for 1 substitution of numbers
for letters. Also you have a lone set of numbers after a ','
which is of length 3. This should serve as a good clue. The
last thing is, at first glance it looks like a lot of different
numbers, but the repetition of 1 and 0 are much much greater then
any other #.

So going on the assumption that a letter is encoded with 3 digits
I split apart the numerical strings every three digits and right
there the cipher literally fell apart before my eyes. Look at the
resulting string and you'll probably have the cipher figured out
before you even look at my key.


310 411 300 410, 301 --- 400 411 610 201 --- 701 411 601, 401 301 311 201 - AIGD

 J   o   h   n ,  I  ---  l   o   v   e  ---  y   o   u ,  M   i   k   e  - 1974


So all that was left was to take the known letters and the clear pattern and fill
in the key!


====
KEY-
====
* = correct for sure

A - 101
B - 110
C - 111
D - 200
E - 201*
F - 210
G - 211
H - 300*
I - 301*
J - 310*
K - 311*
L - 400*
M - 401*
N - 410*
O - 411*
P - 500
Q - 501
R - 510
S - 511
T - 600
U - 601
V - 610*
W - 611
X - 700
Y - 701*
Z - 710

This whole thing was really freaking cool to me. It was like
the Sunday morning puzzles, but real! Figuring I wasn't the
only one who would think this was cool, I posted this whole
story in a programming forum I frequent, and people there
thought it was cool as well.

So we started a little forum game, where one of us would
post a piece of encoded text, with no clues or hints, and
the rest of the forum would try to solve it. It turned out
to be really fun and rewarding to actually solve them.

Going from this I thought it could be really fun to do this
in a more structured enviroment where each thing you solved
revealed more of a story. Kinda, Sunday morning puzzles meet
a Tom Clancy novel. Seemed like a fun idea to me and the rest
of the forum.

And so, Decrypt was born.