What mathematics should we teach?

CLAIM: Until about Primary 5 or 6 (age 10-11), we should teach nothing but Number Sense, Problem Solving, and Patterns. No Measurement, no Shape and Space, no Data Management, nothing. Just conceptual understanding of Number, and skill with composing and de-composing numbers (by number I mean number in all its iterations, fractions, percents, decimals, etc). By the time children get to Primary 5 or 6, they are agile with numbers, breaking them down, using operations, putting them back together, using mental math and written strategies, and solving problems.

SUPPORT: Which type of children excel in mathematics? The children that have number sense. The children who see the patterns. The children who are agile with numbers.

QUESTION: Would students be missing out on anything if we stopped teaching Measurement, Shape and Space, or Data Management? Would a stronger foundation in Number sense actually help support these strands?

(I'm not sure I actually believe any of this, just trying to start a discussion)