動作環境

Windows 7 Pro (32bit)
SmartGit Version 17.0.4 #10132

関連: SmartGit > master (Local branches) への他branchからのmerge | merge解除

feature branchなどのmergeに関して、以下の選択肢がある。

Create Merge-Commitはおそらくno fast-forwardなのだろう。

Merge to Working Treeとは何か?
以下を見つけた。
https://stackoverflow.com/questions/24684410/fast-forward-merge-commit-or-merge-to-working-tree-which-is-the-right-option-t

One of your other options, Merge to Working Tree, I think, would perform the merge, but leave the result uncommitted. If this is what it does, if you then do a git commit, you'd end up at exactly the same point as Create Merge Commit; the former option just gives you an opportunity to edit the commit.