Well if I'm fighting w/ a Team that has rentals they are all new.
I wouldn't place my entire trust on the new to enter a building and complete an assault, I love to fight in close and stare my oppenent eyeball to eyeball.
I would perform some sort of combo between these.

Keep em pinned while squad takes them out!
Try to flank them by going around, squad covers.
Get close, then Mercy them.

Keep them pinned down while my squad moves up and gets into a close and covered position.
Once in postion they supress for me so I can get to them.
Once to them lead an assualt to get in close and stamp them out...I dont do the mercy thing though....no quarter!

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