not being rude but why are you feeding 3 feeds? alfa a oil when fed at the recommended amounts for size of horse/workload is same energy level as competition mix/nuts,but without the fizz from cereal feeds,can be topped up with small amount of naked oats if you need a little more spark.
we...
Think you've got the worm aspect covered,but have you looked at diet to ensure they are getting enough vitamins & minerals which are essential for youngsters.would drop the h&p nuts,as you are probably not feeding or going to feed at the recommend amounts[due to lami] & replace with hifi...
You could try speaking to Louise Morton at Lingbourne Stud,she stood E.Prince & has a wealth of knowledge of his offspring.pm me for her contact details