AE Shoes: same last, same size, but...

[Redwoood]

^^I could imagine this to be true.
To shape a shoe, the upper/liner is stretched over the last. Once you remove the last, the material is bound to contract a little. Depending on what material is used, this effect could vary.

Paging DWFII...

 

[countrygent]

Originally Posted by Master-Classter

that could be causing the slips... The different lacing structures could impact where your foot sits in the shoe. Bal might keep it further back if it's too low, or keep it snug if right. Or, Blutchers may be looser so the foot moves around more, etc. But yes, I don't think it's unreasonable to have it fit a bit differently.

There are things you could do to compensate...
Thicker/Thinner socks, heel/ankle padding, it may be as simple as breaking them in for a few days.

+1.

I have blucher and bal shoes, same size, on the Executive 2 last, and while the foot volume is probably almost identical, the amount of slippage is much higher with the bal, resulting in my comfort level being much higher with the blucher. I assume this is almost completely due to how the lacing distributes tension and pressure in the shoes.

 

[bluesdance]

You could try a different lacing method. Look up Ian's Shoelace Site for nfo.