I don't know how literally you want to take the word "minion," but the RF section (without looking at my book) says that it does not apply to minions.
And Olr Boyz are Troops. :)
Either leave them their True Grit or increase their number of Wounds, because orks going down after taking 12 Wounds at TB 6 is stupid. :)
BTW if you use Critical Effects only for "boss" characters, that makes a lot of the Talents in the book next to useless (like Street Fighter)..
Well the book is as awlays a recommendation - if your players struggle killing orks by crit damage, you can opt not to use it on the hordes and reserve it for important Orks.
As for Talents being pointless, remember that enemies can have the same talents as players and so they will have an affect AGAINST the players!
Ouch, that's poor consolation for the players.
I like the idea of adding wounds to troops with True grit as that's the overall effect of it in the macro scale, perhaps TB/2 in extra wounds that particioned. So the wounds for an ork are listed as 12 (15) and street fighter (or other effects that add critical damage) are applied if you do 13 or more wounds.
Once again this is all assuming the players are using regular lasguns or something equivalent when most will be using a weapon that is a great deal more powerful on top of the extra accuracy and possibly damage provided by their comrades.
I know I stated this in my previous post but it makes complete sense for an orc to only go down after having taken a barrage of lasgun shots. If your players are struggling to kill the orcs then have some npc's possibly from another regiment recommend using different weapons, such as heavy weapons, bolters, flamers, plasma, or weapons with the felling property.
Even the sergeant who doesn't have ready access to awesome weapons can issue orders so that anyone who still has a comrade will have their damage increased by 5.
Any weapon that can on average do greater than 13 points of damage per attack will very quickly take out an orc even with true grit in place. This includes the long las, sniper rifle, rippergun, autocannon, heavy bolter, krak missiles, melta, and plasma weapons. Flamers also work well because of orks have an extremely hard time passing the test against the flame quality and will most likely run around burning after they are hit the first time.