Blade length and old guards

[Janie]

I actually have two questions, but I don't know how to separate them so they're not rather redundant...

1.  Does one blade size go with one boot size? I have new boots in the same length, same width, same brand, but I only just noticed today that the blades are 1/4" shorter! Does that matter? I don't have any trouble with them (so far).

2. Can old guards used on previous blades still fit on new blades that have a slightly different size? As in, since the length is different, the position of the rocker and the curvature along the length of the blade would be slightly different too, right?
I have the Guarddog two-piece skate guards, and with my old blade (10"), I did not have to cut any bit off, I needed the longest it could be. But now on my new 9+3/4" blade, it only loosely fits. I can feel it wobbling as I walk around. Does anyone have the manual and know if it is necessary to cut a bit off for this blade size? I never thought I'd need to do anything with them again and chuck out the manual.
I don't know if it's a length problem though, or a curvature problem like aforementioned, because the guard doesn't fall off the end, it sort of rocks like a boat (but lengthwise). The guards may have conformed to the shape of the previous blade? Any advice please?

[taka]

1.  Does one blade size go with one boot size?

Not necessarily. Some fitters/skaters prefer blades mounted flush toe to heel, some fit blades 1/4 shorter than the toe to heel length. Much shorter than 1/4 (or too long) and the rocker etc will be in the wrong place making things harder for the skater.

2. guards

Guardog guard instructions. It just sounds like they are just a bit too long now and need trimmed!

[Janie]

Thank you taka!! That was extremely helpful!!