I'd say the difference is still rather small, except vs clumped targets and at max range where the PM-41 should be superior. The slightly faster fire rate is definitely a plus for the GRW-34 and may often make the difference between getting another shot in before a team weapon retreats and barraging an empty spot of land. also note that the results in the link refer to barrages into the FoW, in cases where you have vision on the target the scatter difference between both mortars is probably a bit smaller and they should be a bit closer in terms of performance.
Point remain that MP-41 does not need a buff in its barrage.
Relic Entertainment
cblanco ★ 
Heartless Jäger 
