While it is an interesting idea I think I simply would not use it because of its tactical disadvantages.
1. It would just cover one soldier/one direction.
2. As alien weapons will get a huge punch sooner or later agility is critical for everyone.
3. If unmanned vehicles get implemented they will better serve this "tanking" purpose as I suggest.
4. I actually prefer firepower over protection in most scenarios since often first hard hit wins the battle.
I do not consider bunkering a successful strategy by now. The loss of TUs make you a sitting duck (using it's original purpose it would slow down your whole squad behind the shield while advancing).
I could only think of it to be useful on some special maps whre is might be useful to block certain ways or something like this.
Explosive will counter it too easily in my opinion.