I have tried to follow the proposal of Ravels solver first line. I think it solves the puzzle in a simpler way than both RW and myself have done:

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`1. [r1c9]{=8=[r1c4](-8-[r5c4])`

-8-[r2c6]-4-[r8c6]}

(-1-[r9c9]=1=[r9c5])

-1-[r7c9](-4-[r6c9])

-4-[r7c56]=4=[r8c5]=6=[r9c4]-6-[r5c4]-4-[r5c78]

=> Nowhere to place 4 in box 6 => r1c9<>1

=> Pointing pair column 8, r78c8<>1

=> Simple nice loop: [r8c2]-3-[r8c8]=3=[r9c9]=1=[r7c9]-1-[r7c2]=1=[r8c2] => r8c2<>3

I think this Nice Loop is optional for solving the puzzle.

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`2. [r8c3]-3-[r8c8]=3=[r9c9](-3-[r6c9])`

(=1=[r7c9]-1-[r7c256])

{=1=[r9c5](-1-[r8c6])

-1-[r5c5]=1=[r5c6]}

=2=[r9c7]-2-[r5c7]=2=[r5c8](-2-[r6c9])

=3=[r4c8](=9=[r4c7])

-3-[r4c6]

=3=[r6c6](-3-[r6c12]=3=[r5c1]=6=[r6c123]-6-[r6c5])

=2=[r4c6]=7=[box line: r78c6]-7-[r9c4]=7=[r9c13]-7-[r7c2](-8-[r7c5])

-8-[r46c2]

=8=[r6c1](-8-[r6c458])

-8-[r6c9](-4-[r6c5]-9-[r7c5])

=8=[r5c7]-8-[r5c45]=8=[r4c4]-8-[r12c4]

=8=[r2c6]-8-[Naked pair: r78c6]-4-[r7c5]

=> empty cell r7c5 => r8c3<>3

=> X-wing r69c39, r9c1<>3, r6c126<>3

Using the same error net, it also is possible to eliminate 3 from r8c1 and r8c2. However this is not done here because a solver may not see that in this way. This could have maked the solving easier.

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`3. [r5c6]=3=[r4c6]=2=[r6c6](-2-[r6c9])`

-2-[r6c23]=2=[r4c2]{=7=[r4c4](-7-[r9c4])

=8=[r4c7](-8-[r5c7])

-8-[r6c9]-4-[r5c7]-2-[r9c7]}

(=3=[r3c2]-3-[r3c1])

-2-[r1c2](-6-[r1c8]=6=[r2c8])

-6-[r1c1]

-5-[r3c1](-7-[r9c1])

-7-[r3c78]=7=[r2c7]-7-[r9c7]=7=[r9c3]=3=[r8c1]=9=[r9c1]-9-[r9c7]

=> Empty cell r9c7 => r5c6<>1

=> Singles r5c5=1, r9c9=1, r7c9=4, r9c7=2, r8c8=3, r9c3=3, r6c9=3

=> Pointing pair: r12c8<>2, r5c46<>4, r2c7<>8

=> Simple Nice Loop: [r8c5]-6-[r8c3]-7-[r8c7]-9-[r7c8]=9=[r7c5]-9-[r9c5]-6-[r8c5]

=> r8c5<>6

=> Pointing pair: r9c1<>6

=> Simple Nice Loop: [r9c7]-9-[r8c1]=9=[r9c1]=7=[r9c4]-7-[r4c4]-8-[r4c7]-9-[r8c7]

=> r9c7<>9

=> Singles and one empty rechtangle solves the puzzle.

Step 2 and 3 are complex steps, but no more complex than the most complex steps RW and I did. I don't consider them "monster steps".

If you counts only error nets as a step, then 3 steps is sufficient. And then 2 or 3 additional Simple Nice Loops must be used too.

/Viggo