Tough Sudoku for 26/February/2011

This puzzle likely does not require the elephant gun I used to slay it. Nevertheless, I thought some might find it interesting to see an Almost Finned Swordfish in action, so I blogged today's tough. The link to the blog page will appear at the top of the upper right column, directly under the words "Check out the sudoku blog".

Interesting rock fossil! I find them intriguing.

SE=7.6

You might not be a spring chicken, Bev ... but that's no way to talk about yourself!

1.SST to UP25
2.(6)hi5=hi6-(679=8)e469-(348=9)g489 &
-g3=df3 > -9e1
-(489=6)ahi5 > +6hi5, UP34, FXW(5)fh49, -5i4
3.(5)a8=a1-(579)c2bc1=(124)c279 > -1a8, UP81

first step extends chain from (9)g4
I] -(9)g3=df3
II] -(489=6)ahi5 with (6)hi5 on both ends

Steve, reading your blog I see you found the same chain in step 3. Also (rarely?) hidden == als can be found from partition 'pivot' cells such as c2 in today's puzzle which is als == als. Other stranger pairings are also possible.

#0 SSTS ; UP25
#1 (9=7)e5 - (7=8)e9 - g9=(8-9)g3=xwing(9)df8,df3 => df5<>9 ; UP25
#2 hs(79)be4=(9)gi4 - i5=(9-7)b5=b4 => b4<>234 ; UP47
#3 (9=12)c67 -(1)c9=(1-5)a8=a1 - (5=9)b1 => b56<>9, c12<>9 ; colouring(5) ; UP81

Too hard for me.
I had to make two guesses - to save my failing memory I suppose.

That's not a fossil, that's an ancient skid mark, possibly from the very first wheel!

OMG, Dan! You're talking skid marks?

Took way longer than it should have - a little over 30 minutes.

I wish I knew what it was. Because I was standing at the top of a chairlift in Banff National Park, I couldn't collect it to take it somewhere it could be identified. There was a whole bunch of interesting stuff melting out the snow up there.

Would have made a good back scratcher?

1. Note d6/f4=25;df8=69.Unique possibilities to 24.
2. If e4=7,e9=8=i7=g3,g4=9=e6(because locked 9s at df3),i5 has no candidate.So e4=9.UP34.
3. If c67=12,c9=4,b1=5=a8,b8=3,b7=2=c6,d6=5,d7=3;top right box is devoid of 23.So c6=9.UP42.
4. Whether b1=9,a2=2(to avoid the 48 unresolvable rectangle at ab25);OR b1=5=a8,b7=3;b6=2.UP81.