undocument about positon/order comment!?


I am an experienced programmer, but new to MQL,  I am trying  save some private data in comment of position to track later.

As it's undocumented clearly in dcoument,  I googled and did a lot tests, finally  get the conclusion disappointly:

1.  The comment is filled when creating order, and can NOT be modified later.

2.  The maximium length of comment is 32 chars.

If "comment" field were able to be modified, it would save a lot efforts. 

Is the restriction due to save server/network resource?