I have not dealt with GD&T a lot but Max Material Condition would make me think that it is smallest hole. LMC would relate to the material when the hole is at it largest. Let me know if I am incorrect
Max and least material depends on what you are measuring.
Max material condition is used on a hole. If you have a hole that is 1.000 +/-.005 andthe actual diameter of the hole is .995, you gain no bonus as the diameter is at the smallest size. In other words, you have less room for fit error. If the hole diameter is at 1.005 then you gain a bonus of .010 as the hole is at the highest diameter possible.
Least material condition is used on a boss. If you have a boss that is .990 +/-.005 and the actual diameter of the boss is .995, this would gain you 0 bonus tolerance as the diameter of the boss is at the highest possible. If the boss were to actually measure .985 you would gain .010.
Using the two examples above, assuming the boss is going to 'fit' into the hole. If both diameters gain you 0 bonus then you have to put the hole and the boss in exactly the right position otherwise they will not fit into each other. If you make the hole big and the boss small (but within tolerance) you have more room to 'misplace' the hole and/or boss before they will not slide into each other.