Maybe I haven't dealt with comments to the right entry - I use Gmail - but if they did this to me I would switch which email I used for contact at Dreamwidth! I don't really want to lose part of the post I was responding to

GMail doesn't delete part of the message - it only doesn't display it in full in the default, but gives you the option to click on a link ("[Message clipped] View entire message") which opens a new window in a 'lighter' style where you can view the full message. I suppose this is done for performance reasons.