My Mate in 3 puzzles

Mate in 3. Don't move the same piece twice.

#143 is mate in 4, not in 3.

If Black replied to White's first move correctly it would be a mate in 4. However, Black's less than ideal response to White's first move made it a mate in 3.

That's not the issue. Someone who solves the puzzle will calculate in his mind how to mate in 3 before he plays a move. But he will be wasting his time as the solution cannot be found. That's the primary reason why puzzles need to be perfect!

Let's agree to disagree. I don't believe puzzles should be calculated perfectly before the first move. I think a puzzle can be played based upon the moves of the opponent. For example, a mate in 3 might have two solutions based on the opponent's response to your first move. I don't think puzzles should only contain forced moves that can be calculated before the first move is played. However, I'd never include a blunder within the puzzle. If the puzzle is a solution in 3 moves there will be no blunder moves by the opponent in the solution.

I guess you say that a lot to people. Most things in life are not a matter of opinion and therefore not of (dis)agreement. Subjects start with definitions. No one shares your definition or understands your definition of "Mate in 3 puzzles" as you make it up on the road. How did you ever end up in chess rather than crocodile hunting? 

Mate in 3. Don't move the same piece twice.

Which puzzle?

This Mate in 3 has 2 solutions based on White's first move. In solution #1 check the Black King with your first move.

In solution #2 pin the Black Queen to the King with your first move.

Mate in 3 by White. Every move by White must be a capture.

Mate in 3. Don't move the same piece twice.

Mate in 4.  Every move by White must be a check or capture with check.