He seemed to be on the cusp of the first team at the start of the season Eggs but has fell well down the pecking order, maybe more regular U-23 watchers than me may have a better idea on what's happened!
I think Koeman had a look at him pre-season and felt he was a bit off the pace when it came to the pressing side of the game. To give the pessimistic analysis, while this has improved he is still some way off where you imagine Koeman wants players in the first team to be. It's also fair to say his form in the under 23's is not as scintillating as last season where he was scoring goals and ever hatricks quite regularly. I err more on this perspective and do worry Dowell may not get too many chances under Koeman but we will see.
To give the more positive outlook you would say he looked decent in pre season games (I thought he did well). Koeman was initially quite reticent to give young players too many games, and the likes of him Davies & Kenny were pushed to the back of the cue. It's not unreasonable to suggest this was a wider strategy- namely to give all the senior lads a chance first, bomb out the ones he didn't fancy before allowing younger players a chance to play and not be caught up in that process. If thats the case it may be that lads like Dowell may get another look in come the pre-season. This season Dowell has also grown up a lot physically. I think form dipped as he had growing pains but he can come back a bigger, stronger player.
I think Dowell and Walsh are problems in some ways- for different manifestations of a similar reason. They are probably the two most talented young players we have, but there is an issue with their physicality in doing what the manager wants. I imagine both will have tempting offers as well, so we will see how it develops.