For a movie that is filled with nonsense & inconsistencies on the important stuff, they are pretty consistent and honest on this, up to a point. They tell you up front he has gotten the automation system going, and that he can finish refitting things or complete repairs to make her spaceworthy in two weeks. That all fits with Kirk's intent to go back out and his belief (in contrast to Morrow's) that the ship can hold up.
In all this, you've can extrapolate that Kirk fully intends to go back, otherwise why bother with all this rush&fix-it stuff?
But there's also one bit of delusional thinking on the part of Scotty & Kirk ... the 'didn't think you'd be taking us into battle' part. In this Morrow turns out to be the one with his head on straight. In the movie era it seems almost a given that if the ship is going anywhere, it is going into battle. I mean, even as a passenger on a training cruise it winds up in battle. It is the ENTERPRISE. It is gonna wind up in battle, even if it is just shooting an asteroid in a wormhole.
Then again, it is just as easy to ascribe the easy crippling of the Enterprise to Bennett's bad writing. I remember a Trek novelist (the one who wrote the ALL OUR YESTERDAYS sequel novels) bitching about why they didn't have a real pitched battle before the stuff shorts out, and it is a very valid criticism, especially since you'd want more sturm & drang to offset the increasing stupidity that follows, like beaming down to a distintegrating planet and THEN trying to negotiate your way off of it, instead of beaming to the BoP and taking it over directly.