well if you dont mind possibly introducing dirt and what ever else is on the rope. plus, how do you know your not putting too much pressure on the top of the piston? cast pistons mite not take the pressure as much as a forged set. but,..in a jam, definitely doable. never heard of the rope thing. neat.
Just dont turn the engine over with the starter when using the rope trick. Big rookie mistake. Learned that the hard way.
If the retainer is wedged tightly to the keepers, it may push the valve into the hole when you compress the valve spring to remove the keepers. I hold the cyl at TDC with a breaker bar for this reason only, JIC. A smack with a hammer and socket usually prevents this but every now and then...
