The makef vs. the requirement not to run the words of Shema together

From Shema, and within parshat va`etchanan:

ה וְאָהַבְתָּ, אֵת ה אֱלֹהֶיךָ, בְּכָל-לְבָבְךָ וּבְכָל-נַפְשְׁךָ, וּבְכָל-מְאֹדֶךָ.

5 And thou shalt love the LORD thy God with all thy heart, and with all thy soul, and with all thy might.

Minchas Shai notes an interesting tug-of-war between the requirements of dikduk and the requirements of halacha:

בְּכָל-לְבָבְךָ -- When Raza"l said that one needs to place a space between the connecting {letters in Shema which phonologically are similar or identical and might stick together}, they did not mean to pause such as not to put a makef between the two lameds as it is. For if one reads it without a makef, the nikkud {under the khaf} would be a cholam {rather than kametz, or rather kametz katon}. And this Raza"l did not say, to switch the vowels which were given to Moshe from Sinai. Rather, even though you should read it with a makef, you should place a space and distinction between them linguistically, so that it is apparent that you read two lameds {rather than one}.

This seems correct and entirely possible to do, though even without the makef {and resulting loss of stress on the word kol} one could still pronounce it as kametz rather than cholam. Also interesting how he adopts this position that the nikkud is miSinai, where there might be debate on this subject.