Been doing a little bit of analysis on the composition of 2015 World Cup Squads by position and I think the insights give us a pretty good idea of who EJ is likely to take. For those interested I looked at the squads for the 6 nations teams, rugby championship teams and Japan (11 in total).
Prop
Every team except Japan started the tournament with five props. In most teams, at least one of those players could play both sides, which I'm not aware of any of England's current squad being able to do. Despite that and given Eddie's decision to take only 4 with Japan, I'm confident we take five.
Avg. in Squad: 4.91
# in Eddie's Japan Squad: 4
Predicted for ENG: 5
Probable Players: Vunipola, Marler, Genge, Sinckler, Cole
Hooker
Three is the magic number, unless you're Wales or Argentina. The Pumas actually ended up requiring a medical exemption to field an eligible team in the bronze final after one of their two hookers was injured. Even with Hartley remaining unavailable, I'm sure we will take five.
Avg. in Squad: 2.82
# in Eddie's Japan Squad: 3
Predicted for ENG: 3
Probable Players: George, LCD, Singleton
Lock
In 2015, teams averaged 9.45 "Back Five" players (Locks, Flankers, No8s). Most teams allocated four of those spots to Locks. The two teams who took three - New Zealand and France - had obvious Lock cover in the Back Row. Wales inexplicably took five Locks, alongside six Back Rows - probably because their exciting attacking game plan required the flair and invention that only these positions can bring...
Avg. in Squad: 3.91
# in Eddie's Japan Squad: 4
Predicted for ENG: 4
Probable Players: Itoje, Kruis, Lawes, Launchbury
Back Row
This is the first position where the analysis suggests there is scope for some variance. The average trends to six Back Row Forwards, however if ignoring the teams that took just three Locks, that moves to 5.37. Combine that with the fact that to take six would require two rookies (Ludlam and Dombrandt) both making the cut, and I don't see it happening. Dombrandt will make the cut in my opinion, although there is of course the chance that Ewels is added instead as an additional Second Row, but given the additional positional flexibility of Dombrandt to cover 6 and 8, I think this is unlikely.
Avg. in Squad: 5.55
# in Eddie's Japan Squad: 6
Predicted for ENG: 5
Probable Players: Wilson, Dombrandt, Curry, Underhill, Vunipola
Scrum-Half
Another somewhat disputed position in terms of the "right" number to have in a world cup squad. The consensus landed closer to three than two and I'd expect Eddie to agree, despite his choice to take two with Japan in 2015. That decision seemed to be based more on lack of quality options than a grand strategic play. It also makes absolutely no sense to bring Heinz into camp and waste practice reps getting him up to speed only to have him sit at home for the World Cup, when we've already got an 84 cap international doing the same in Care.
Avg. in Squad: 2.64
# in Eddie's Japan Squad: 2
Predicted for ENG: 3
Probable Players: Youngs, Spencer, Heinz
Fly-Half
Whilst this has been a matter of considerable debate among English fans, it actually seems to be quite clear cut. Only three teams took three Fly-Half's and for two of those teams, the third Fly-Half could and did play in another position (Lambie and Barrett). Only Ireland took three out-and-out 10s and that was with the most injury prone starting Fly-Half since Sir Jonny.
Avg. in Squad: 2.27
# in Eddie's Japan Squad: 2
Predicted for ENG: 2
Probable Players: Farrell, Ford
Centre
This one is pretty clear. Only Wales and South Africa took three and they both had to call-up at least one injury replacement during the pool stages. Don't be stupid, take four Centres.
Avg. in Squad: 3.91
# in Eddie's Japan Squad: 4
Predicted for ENG: 4
Probable Players: Tuilagi, Te'o, Slade, Joseph
Back Three
I've combined these because it's too misleading to split Full-back from Wing, given how many squads listed Wingers that were competent international Full-Backs and vice versa. I think this will be relatively straightforward from an England perspective and pick themselves if fit. The one question mark is Nowell who, if injured, I see being replaced by Brown.
Avg. in Squad: 5.00
# in Eddie's Japan Squad: 6
Predicted for ENG: 5
Probable Players: May, Watson, Daly, Cokanasiga, Nowell (Brown)