DESCRIPTION:
When editing the sequencer with multiple embedded metastrips, automatic adjustments on one metastrip can effect the contents of an embedded one, (these automatic motions occur to prevent an overlap) resulting in swapped order of strips and occasionally overlapping strips.

STEPS TO REPRODUCE/OBSERVE
1-load the file testmeta.blend (attached with the report)
2- observe that the strips "botchan3" and "botchan4" are on channel 3 and 4 respectively
3- press tab to get out of the current metastrip "m1_chan2"
4- select "midchan3"
5- press tab to get out of the current metastrip " m2_chan3"
6- to trigger the bug, un meta (alt-m) "m2_chan3" notice strips have moved (somewhat haphazardly/undesiredly) but at least you are seeing what the results of your actions are (not perfect, but not the bug)
7- select "m1_chan1"
8- press tab to go into it

RESULT
9- observe that botchan3 and botchan4 are now overlapping on channel 5

EXPECTED RESULT
- "botchan3" and "botchan4" should remain on channels 3 and 4 respectively, as they were in step 2.

VERSION
This effects the current SVN checkout rev.30982

OS/System:

Ubuntu GNU/Linux 10.04LTS "Lucid Lynx" Intel 64 bit quadcore, nvidia GFX

NOTE
combined with bug #21481 and bug #21475 this is getting the sequencer into 'deadlocked' situations, where the combination of these bugs makes you 'chase' stuff around, sometimes for an entire day or more (in a complex edit) because as you 'unbreak' one thing, you accidentally break the other, or get yourself into the situation where the other bug manifests itself.