I'm sorry. I'm cleaning up my messy post right now! (It was spilled with excitement and nothing about analysis etc. I want to stay on this forums)
So at first:
I downed Noth on my third try. No Problem at all.
Then I killed Heigan 25 man Naxx. For this try I had to switch from my shale spider to my Tank Beetle and had to transfer a point in 2/2 imp mend pet (but still being BM). The damage with the dot may be abit spiky and my shalespider died two or three tries because of: 1/2 imp mend pet and just 1 shild wall (cower)
This fight is just hard because of the time it took to down him (~25 Minutes give or take 2-3 Minutes).
I then tried Loatheb (10) and this fight was very exciting for me. It's my first time I tinkered my own strat and made it work:
At first: He IS soloable (proofs following after the rendering and my sleppytime is finished), BUT he is (maybe even VERY) gear and preperation dependant right now. I'm in good heroics gear with 2 pvp items and a few epics right now and it took me close to death to down him. I made a lot mistakes as seen in the video, but the strat breakdown comes to this:
1) You want to down him ASAP and this could be realized by the spores which reduce your produced aggro to ZERO (very important) So I choosed my typicall Raiding SV package.
2) Have a load of pets ready! Since you can hardly heal your pet the magic trick is the following one: I started with my Tank beetle and used harden (is it the correct translation??) and cower nearly on cd. Mending him nearly before the debuff runs out. This isn't enough though. I then DISMISSED my pet infight at a good distance.Here kicks the spore debuff in since you do not generate aggro at all. (I had just my DPS pets ready at this point of time) They will start with: Full health and No debuff. So using cower and mending pet is very advisable, but also is the timing (I messed it up here pretty hard I think). So switcing pets right after the debuff is applied may be positive, but:
2a) I had to cycle alot. :-( This is caused by the fact that the pets were not tenancy pets but fero or cunning pets. I switched to my tank beetle later in fight and he might reganed life but started with a ticking debuff. So timing moght be the key again.
I think this fight will become quite trivial when:
-you have just turtles and beetles.
-your gear is better.
-you time your cycles better than me. (shouldn't be hard) ;-)
For the kill I also used:
My gear (shild tinker on belt - but ignorable)
A healthstone
A misused mystical healing potion with glove tinker (macroed the glove slot to attacks. BIG mistake on my end)
A Flask of endless rage (180AP flask - leftover from wotlk raiding)
A couple of pets

My ingenuity ;-)
And alot of faults and "screw-ups"
What also played negatively into my cards was the time. it is 5am right now and i downed him at 4am. Way too late/early!
So my PC is pre rendering the xfire file (which my vegas denies to work with

)I'll do some sort of polishing and editing but the whole fight will be seen.
When I'm done with sleeping.
Ohh and i almost forgot:
Merry Christmas. Feliz Navidat. Frohe Weihnachten.
/€dith:
The Loatheb Video should be online now:
Endriel VS Loatheb