Details
The vastly differing team situations makes it especially tough to compare Richard with Hull. With the search function down, I can't find it, but articles recently posted from the 1960s indicate that it wasn't uncommon for Hull and Mikita to see 40 minutes of ice time in particular games due to Chicago's lack of depth.
I think this does an awful lot to explain why Hull and Mikita have traditionally been ranked lower than what their raw stats would indicate. (I mean in traditional historical canon where, for example, Richard is often thought of as the 4th best forward of all-time, not on HOH where it has practically become canon that Hull should have that title).
I have also seen it posted fairly recently that all the ice time in the regular season was sometimes blamed for Chicago's stars being burnt out by the time the playoffs hit.
So Bobby Hull's case over Richard (better regular season stats) and Richard's case over Hull (more individual contribution to team success) could both largely be functions of Montreal's superior depth.
Rather limited analysis especially given that the careers of the three players shared at most three seasons.
The details reveal a somewhat different picture.
The basic issue is whether a coach uses his star forwards to kill penalties. The Canadiens with Dick Irvin Sr and Toe Blake did not use the star forwards to kill penalties. The two penalty killing forwards were a blend of the two extra forwards or 5th defenseman - John McCormack, Don Marshall, Floyd Curry, Bob Turner, Jim Roberts, Red Berenson, etc. The other teams tended to use their star forwards in PK situations at least partially.
This impacts at two levels. PK is more demanding/tiring since the workload of 5 players is split amongst 4 and it disrupts the lines for the next few shifts as the line rotation has to return to sync.
So while Bobby Hull and Stan Mikita may have had greater TOI totals these extra PK minutes did not produce significant offense.
SH goal data has been kept since the early sixties. Henri Richard and Jean Beliveau total 0 SH goals while Mikita and Bobby Hull are amongst the SH goal leaders for the era.
Depth was not a factor in such decisions. The Hawks at various points during the Hull/Mikita years had qualified PK players on the roster - Earl Balfour, Glen Skov, Reg Fleming, Bob Turner, Lou Angotti amongst others like Eric Nesterenko, Chico Maki, who were regulars, but chose to use their star forwards.
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