Seems like a lack of situational awareness, yes it's the general aim to score runs - but in this match, in this moment, the aim has to be to survive - ergo play at nothing you needn't play at. Everything with soft hands, and just swallow up the pressure. Jennings fencing at a ball that was never going to hit his stumps on height looks terrible. Do rate him as a player though, think in the CC he's a top player, and understandably worth a crack in the Test side, but thus far he still has some work to do - still young though, could get there eventually.
Not sure whom else they could pick as an opener. Burns is the obvious one I guess, must've earned a shot by now. Mitchell at Worcestershire is in good nick, as is Clarke. Would love to see them pick Hildreth and Mitchell, give some experienced players a crack at stepping up, rather than pinning hopes on the emergence of a 20 yo superstar every few weeks. Certainly worked for Voges and Rogers.