Of course. The majority of listeners won't even notice. Only ones who are very familiar with the piece will notice something. I loath it when commentators toss around "composer's intention". How can anybody really know anyone's intention, unless that person makes it very clear in writing, or in person. I'm convinced Mahler didn't fully understand what he himself had composed, half of the time. There are many things he said 'off the cuff', that make me think that. Regardless, the score to the Adagietto not only has "langsam" and "sehr langsam" written in it, he also wrote "Molto Adagio" twice - once at the beginning, and once at the return of the "A" section (the recap). "Molto Adagio" doesn't sound very swift to me.