Macfusion does connect to SFTP servers, using SSFHS (not to be confused with SFTP), but Macfusion is not directly comparable to SFTP clients. And so on…
Exemplary of a factor (in this case, NCP - Novell Core Protocol) that could not be guessed from the client perspective, and that may lead to puzzling behaviour when MacFUSE and applications such as Apple Finder are added to the equation.