As an aside, I don't think this season's Robshaw is pulling up trees at all. Statistically his numbers are nothing special these days compared with the alternatives. Everyone makes a huge number of tackles, and his carrying is not what it used to be. Just to look at his last 3 starts:
v Tigers, 9 carries for 14m, 7 tackles made / 1 missed
v Wasps, 4 carries for 3m, 8 tackles made / 3 missed
v Ulster, 5 carries for 4m, 9 tackles made / 2 missed
He is nowhere near the player he used to be and having him at 7 is a bit of an issue for us as he's gotten slower. I have huge respect for his skills and his game nous but it seems fairly clear to me that his injury ended his England career and he does not look like he should be back in the squad.
However, what Dombrandt brings is a combination of tackle-busting power, great lines and offloading, and breakdown skills. This means he's a live option for number 8 or 6, and our "classic" 6 and 8 options are not that deep. For 8, we have Billy and Nathan Hughes, who both have their issues, and then the completely different Sam Simmonds who might not have the game for international rugby. We've learned time and again that we need an alternative to Billy so 8 is a good shout for him, and it's also not somewhere where there's loads of quality youngsters banging on the door.
6 is a different story, Eddie likes his dual opensides so both the Curry twins are in the mix, as well as Jack Willis, then you get youngsters like Ted Hill at Worcs who's seriously impressive and maybe the Bath kid whose name escapes me too. It's more congested for sure.