I disagree.
Having had the transmission in-and-out twice at the end of August, and having assembled, disassembled, and then again reassembled the steel-bar engine brace we used, the results were the same both times.
Ryan (
91 Plus) can verify the interference problems we had in only using two jackstands when trying to install the subframe and line-up the engine/transmission mounts, as well as the limited space in working under the car - because you simply cannot elevate the car very high with only two stands.
Perry (
pjtoledo) can also verify that the engine brace (which he made

) was installed correctly. His brace provides two locations for supporting the engines using chains, lifting hooks, and clevis pins - one directly above the the engine's left-front factory engine hoist bracket, the second directly above the engine's right-rear corner, where the 10mm bolt is bolted into the head (95 MTX). These are the exact same two locations that SDpatt uses in his homemade wood-engine brace, and is a very well constructed home version of the one that pops-up on ebay.
Additionally, both Ryan (
91 Plus) and Matt (
98shotoy) can atest to how little room there was under the car with two jackstands, when trying to remove and re-install the transmission.
First, I disagree that having the vehicle on only two jackstands and chocking the rear wheels (were the car is on an incline and the rear wheels can still rotate), that the vehicle is going to have more stability than when sitting level on four stands. I've never had a car "creep" backwards on four jackstands, like it does anytime your raising or lowering the vehicle to place it on two stands, or on those occasions where the rear tire chock gets inadvertently kicked-out while you're working underneath. Unless the stands are on an unstable surface to begin with - or you have people playing full-contact tackle football around the car - it's not going anywhere on four stands.
Second, the amount of workspace lost (unless you unsafely elevate the vehicle too high) is at best two inches, maybe three at the very front of the front bumper, which can easily and safely be compensated and exceeded when using four stands. We never had a problem reaching any items from below - if anything the problem was not having enough room underneath to maneuver to reach upward. The workspace aft of the rear subframe mount becomes progressively less, and the amount of workspace below the shifter assembly was marginal at best. None of this is the case when I've used four stands in the past.
I did not experience any of the problems you describe. It will not happen if you use an engine brace like the one I bought for the job that has a front and back lifting chain.
If it worked well for you that's great, but IMHO, four jackstands is counterproductive because when you raise the back of the car, that reduces clearance in the front for getting the transmission out, so you have to raise the whole car higher, which makes things harder to reach from below. I also much prefer the stability of keeping two wheels firmly on the ground if I'm going to be underneath the thing working.