Some thoughts on the extended cross (w/ video)

Subject: Some thoughts on the extended cross (w/ video) Sun May 25, 2008 9:07 am

I don't exactly know why some people are so interested with the extended cross, especially here in the forums. For one, I truly believe that the only people who must study it right now are the ones who are really, really fast (think JB or Chia) because I see no point in trying to establish an xcross when it's just gonna save you 5 seconds or so when you're just sub-30. Large deduction from the time, but not worth the loss of good inspection and look ahead time.

Anyway, this post is mainly due to a request from one thread (sorry, tinatamad akong tignan kung sino, si bnonymous yata yun) na gumawa raw ako ng video. Actually, tinatamad lang talaga akong gumawa, pero since masnakakatamad ang wala, gumawa na lang ako from some random scramble from JNet (Oo, random siya at di ko kinuha somewhere; check the JNet window, ang dami dung 0.xx na times dahil naghahanap ako ng magandang xcross sample) ng semi-tut.

Now, two points that I would like to debunk:

1. Color neutrality - Some consider this an advantage. I beg to differ. While this can be trained (this comes naturally to others, ie. Thrawst), the biggest downside of color neutrality is that you immediately see a lot of pieces and all their possible movements. This seems good at first, pero sa totoo lang, it forces people to inspect in a different light. I cannot explain it enough pero suffice to say that it does not "strike" your eyes as well as white (kung white cross ka). This is especially true for people na nagsisimula pa lang sa CN training or hindi talaga natural ang CN sa kanila.

2. Block building - I also started using the Petrus block to make xcrosses, kasi ang simple ng concept. Build a block, then bring down two edges. What I failed to anticipate that time was having a block but ending up with edges in bad positions (bad orientations, no "chains", one face away, etc.), resulting into insanely high move counts (15 moves for an xcross? Not worth it.). Ang nakita ko rin ditong problem is this: it must go hand in hand with CN. Why? Because if you're a single color crosser, the hard part is actually looking for a possible block. Then balik na naman tayo sa argument ng CN and umikot na etcetc.

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When I do see an xcross (see, because I do not attempt it with every scramble), I usually see it from another angle: "good" second layer edges, or second layer edges that are at most only one move away from their correct position. The reason is pretty simple: You can try to rotate it an indefinite number of times to connect to its corner (Note: Only if the corner is EASY to conjugate) and it won't have to leave its place. Kumbaga, iwas iwas lang. This is better kung may good cross piece pa siya na kasama kasi mabilis niyang "maiikot" ang faces kapag gumawa ka ng cross "chains".

Ang disadvantages nito, marami at malaki rin. The basic disadvantage is dapat meron kang intense imagination. As in sobrang sobra. I don't have that either, pero ang dami ko nang ginawang attempts dati so meron akong idea kung paano magikot ng corners and edges along with the cross. Second is hindi siya always possible (pero palagi ko na lang sinasabi 'to). Third, may chance na lumaki ang move count mo kapag nagkamali ka dahil kailangan rin ng anticipation and lookahead.

Ang advantage lang nito is few, but quite big: Hindi kailangan color neutral, kung tama ang pagkakagawa, pwedeng isabay na sa cross, mababang move count (sobrang baba, sa video ko, 9 moves xcross lang), hindi mo kailangan gumawa ng blocks, at may chance na at least ma-preserve mo man lang ang isang pair kung di mo talaga maipasok sa cross phase.

Tama na muna sa salita. Tinatamad na ulit ako. I'll just upload the video and post it here. Scramble and solution are in the description. Any comments and uproars are most welcome.

As a sidenote, the first scramble in both the 7th and 8th PCAWCs have xcrosses (actually, just pairs that can easily be inserted). I advise that you check them out dahil sobrang dali lang (My PB was there and it was an xcross attempt, clocked in at 12.79s). Thanks.

_________________
3x3x3 SS: 12.79s, 12.12 (PLL skip)
3x3x3 PB ave.: of 10, 18.37s; of 5, 17.62s
Official WCA Record

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No, my pic is not edited. I've got red eyes! Beware, spammers!

6x6x6 Age : 15 Joined : 28 Jan 2008 Posts : 1199

well said kua jome... kung wala kang mkita na xcross wag mo ipagpilit mag cross ka na lang kasi sayang ung inspection time... i agree to what kua jome said... every last detail of it
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palakpakan:)) i learned some useful stuff. thanks
kuya jome... i do what you showed sa vid.. the reason kung bakit i avg 18-22 is mostly because pangit ang last layer ko kaya bumabawe na lang ako sa Cross tsaka f2l

@jemay... yan yung isa pang approach na sinasbi ko:))
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No prob. Hope it was useful. Any more requests, pwede kong gawin kapag may time and di ako tamarin. Haha.
_________________
3x3x3 SS: 12.79s, 12.12 (PLL skip)
3x3x3 PB ave.: of 10, 18.37s; of 5, 17.62s
Official WCA Record

Will kill spammers for free.
No, my pic is not edited. I've got red eyes! Beware, spammers!

I use xcross if i can see it easily on inspection...mostly i focus on 1st pair look ahead while doing the cross. Interesting stuff here.
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"There is no such thing as destiny, only choices."
ACCOUNTING, LAW, TAXATION vs. CUBING

I learned this lesson the hard way and it was 1 year in the making, RCPO2k7 and RCPO2k8. When you are in a competition, drop your cube correctly as much as possible, a +2 really affects your average so much that it's better to stay away from it. 2 seconds is really a big difference I tell you.

I love you Halley.

Sir Jome thank you po sa thoughts na binigay mo po... Very Happy

tatandaan
ko po na wag ipipilit ang X cross kung wala pong mahanap...gawin na lang po ang simpleng cross.... Very Happy

happy cubing po ....

Last edited by jolo_mat2008 on Sun May 25, 2008 9:25 pm; edited 2 times in total

sir.. thanks po sa tuto..madami kong na22nan..

alam ko na ang gagawin ko..mag x cross lang kung may nakikitang easy or obviouse na x cross.. Smile

kung wala..be satisfied with a normal ,less than 8 move, cross.. Smile

tnx sir! sobrang helpful nito..ako po ung nagpost ng thread asking for tips and suggestion about x cross sa speedcubing..pero c jusay po ung nagpost ng vid sa vids section tapos c bynonymous po ata ung nagrequest ng video from you..tnx po uli!
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i'm starting to get sub20 solves w/ xcross happy happy

wow...galing mo kuya..hehe...^^...thx for the vid...learned a lot..^^

i only do the extended cross pag maganda ung situation, ie meron nang CE pair na umaaligid at madali (take note: MADALI) siyang idikit to form a 2x2x2 block. hassle kung di ka pa sanay. focus na lang muna sa look ahead. mas malaki ang time na pede mong masave thru look ahead than thru forcing yourself to do an xcross. hope this helps cheers

btw... ganitong klase ng mga tanong ang masarap/nakakaganang sagutin.

6x6x6 Age : 15 Joined : 28 Jan 2008 Posts : 1199

jolo_mat2008 ndi ka naman noob e..
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I REJECT YOUR REALITY AND SUBSTITUTE MY OWN
thanks to sasori for mythbusters siggy
96% of the teens today like rap copy this to your sig if your part of the 4%

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(> < ) This is Bunny. Copy Bunny into your signature to help him on his way to world domination!

i rarely do xcross, unless i notice a paired edge and it's easily executable. but i concentrate more on the first f2l pair.

to people who aren't that fast yet, don't worry on studying many many advanced things such as ZBF2L or COLL or xcross because right now, you're getting your basics down.

the time will come when you will know that you will take your next step in this world of speedcubing.

@Jome

very well said.. cheers