Counting is music is a learned skill that then becomes an internalized skill, bit like learning to read with your finger to follow the words, you will lose that habit and learn to see the words in the sentences.
Practice counting your meters to 50 in your head, so
1-2-3/2-2-3/3-2-3/4-2-3/5-2-3/6-2-3/7-2-3/8-2-3 etc to 50-2-3
now the problem as you get past single figures is can you say the number fast enough to stay in time?
Answer, well not always, depends on the tempo, but what you do learn is to internalize or recognise where you are or should be.
Its like if you see beamed 32nd notes at speed, you cannot say the notes you see, in the tempo of the song, but you recognise and play them anyway because you learned to internalize what they look and sound like. So practice more intense pieces and if none exisits..... write your own. The act of writing them out will help internalize your skills as a reinforcement of what you are learning.
If the counting is causing you problems then map out the song and then your own count. 1-2-3 can come round a bit fast so when counting in seq, say like 1-2-3-2-2-3-3-2-3-1-2-3-2-2-3-3-2-3 all you have to do is change the map.
So 1-2-3-2-2-3 could be 1-2-3-4-5-6 then you map out everything to suit this count, so you may count for longer phrases but use less maping ( 100 x 1-2-3 or 50 x 1-2-3-4-5-6)
Also phrase inflection is a good reference, certain words and phrases will suit a particular time sig to help set up the feel. counting in numbers is just a representation, (1-2-3-1-2-3, could become, i see you. you see me, because it can be pronounced a I-C-U-U-C-me) it can be anything.
Problem is if you are counting to a point ( ie 62 bar rest) then you will need to trust your counting skills, or have a great mapped alternative so you know exactly where you are.
It is all time based learning, a leap of faith learning as i call it, because it can't be proving that any one person will get it/develop it till they do the time...only then can it be re-evaluated if need be.
