LMGTFY is just a tool -- it can be used in good humor or malice. This site, likewise, but it has the added benefit of promoting DuckDuckGo and producing brand exposure, and is therefore less likely to be taken as a slight; with LMGTFY, everyone knows what Google is, so they don't take that as an informative thing; with LMDDGTFY, few people know what DDG is, so they may just assume that the linker is humorously and conveniently promoting a new search engine out of personal preference.
I see the interest in promoting DDG, but the "let me take your hand and do that for you" is and will always be a bit condescending.
You can tell about a great search engine without that kind of approach, in my opinion. Because if your intention is good, this way is hardly the best, I think. Most will use it like others used lmgtfy, or a more strict "RTFM", years ago: as a "search yourself noob" end of discussion.
I kinda disagree. There's a difference between saying "search yourself" and "search for yourself using these keywords"
And depending on context, some people really do need to be shown that they can type keywords into the search box like so in order to get results like these.