Yes and no, Yes, you never know how someone is going to react in a real game until they play in real games. That is as true as the sun rising and setting. But, whether he shows well or poorly, the long term projections are still going to be based on what they think they know about him from practice. Can he learn from mistakes, how quickly, does he accept coaching, how does he throw etc.
If comes out and balls out, does it mean it's all good? Maybe, maybe it just means defenses were playing learn the qb football and now have 5 games of tape for the rest of the league to study and he comes out next year and everything he went to in high stress situations, they take away. It happens year after year in this league. Can he adapt, handle the stress, accept the coaching, retain the knowledge? I think they have a good feel on that already. Games are higher pressure situations and you can't simulate that in practice. But then some guys learn to work thru that, and some guys don't. Very few are good with it to start with and takes time. Rodgers, Peyton, everyone. It's a rare duck that is a finished product and while 5 games might give you some insight, it might just muddy the waters too because it's enough time to stress the weakness, but not really enough time to finish the product either.
On the flip side, he could come out and suck. Throw the ball well, but turn it over a lot, mis some reads when the first one isn't there etc. He makes some plays, but we score very few points etc. Does it mean he's going to suck long term? Well that depends, can he accept the coaching, learn from mistakes, retain the information etc.
So i stand by my original comment, the fans "need" to see Love in these games more than the staff does. and in the end none of us will really know until he's the guy doing it week after week after week.