“Tantouchokunyu” means that you are direct to ask. There are many other English expressions for this such as a word of straightforward
You come straight to the point.
I asked him point-blank.
This idiomatic expression comes from the old Chinese story that a soldier took his single sword and slashed into the enemy alone. So, the each kanji character of 単刀直入 shows “single” “sword” “direct” “enter” to express the above meanings. From the same pronunciation, there is a misunderstanding to apply a kanji character of 短 for the first one which means a short sword. The soldier did not slash into the enemy with a short sword but one single regular long sword.
You may experience that the Japanese are not good at speaking their opinions straight. It might come from their custom to respect their harmony with others, not to harm their opponent's feelings. But unfortunately, it might not work well at a discussion in the international community.