Shas'o Mont'Be'Gel wrote:Kroot would get massacred by Choppa Boyz on the charge and could (italicized, because it's a very real possibility) even provide the Orks with additional consolidation movement, something you don't want really.
Small units of kroot get massacred by pretty much anything and are best kept for objective grabbing. Large units are another matter.
If you want to use kroot as an actual weapon and not just as cheap objective grabbers then you do need to give them a bit of support and you want to run them in decent sized units. Charging into a blob of 20 kroot with ethereal boost and some markerlight support is painful experience, the psychological impact of dropping 60 dice on the table should not be underestimated. The problem orks have with this is staying in charge range after the overwatch.
As for consolidating - they cannot consolidate into or through another unit so put more kroot in a 2nd rank to block them. Then you have your more expensive Tau sitting behind in support roles - with a bit of kroot conga line trickery you can keep everything in supporting overwatch range.
What I am learning about kroot is that if you want to invest any significant points into them you need to build around them to make them work. Do that and they can be effective due to the sheer number of them you put on the table. It is a shooty horde army with support from the most shooty codex in the game. The fact that they do not utterly fold to everything in the game in CC is just a small bonus.