I'm no expert but I do have recent operational experience commanding a tri-service unit in a dismounted close combat role.
When it came to pre-deployment training and assessment, all physical activity and tests were undertaken on a gender, age and capbadge neutral basis. This meant that all personnel passed to the infantry standard in terms of weight carried and times achieved; hard work to get there but achievable if (as we were) you are trained and prepared over sufficient time and with a PT programme designed to take in to account that not everyone deploying was a 20 year old infantryman. Our PT instructors were outstanding in terms of building-up specific areas (ie upper body strength for the females, knackered knees and ankles for old-timers like me) at a sustainable tempo. As a consequence, I have no doubt that there is nothing to prevent females being physically capable of undertaking the role of frontline infantry.
The issue of unit cohesion is, in my opinion, a complete red herring. Both in barracks and on deployment we have for many years had males and females living eating and sleeping alongside (and sometimes with) each other. Unit cohesion hasn't broken down and there doesn't seem to have been a detrimental effect on operational efficiency. As for how the blokes would react to a female member of their unit being wounded, having been in that very situation myself all you care about is that one of your team is down and gender doesn't come in to it.
The appropriate person, appropriately selected & trained and with the appropriate kit - gender shouldn't come in to it.
MB