First of all, there is no condition of accepting the existing constitution because Gyane has interpreted it to get his own way. New constitution must be drafted and the monarchy must be abolished. Accepting the offer means accepting defeat fully. You educated fools can't even figure out that. These parties might have rejected the offer because of their own squabble. Still, the decision seems to be very appropriate for the given circumstances. If Gyane can't even say that Constituent Assembly is acceptbale to him, the party leaders are 100% right to ignore this offer. By repeated abuse of the constitution, that's what Gyane has established of himself. Parties could be inefficient but look what ground they are speaking from. They can be picked up by Gyane's army anytime. It's not simply Maoist agenda, it's what acceptable to majority. If Gyane doesn't fall in that majority, it's his problem. People are willing to suffer more to guarantee their rights. They are not going to act on Gyane's gesture anymore.